Chemistry

Chemistry: The Central Science | 13th Edition | ISBN: 9780321910417 | Authors: Theodore E. Brown; H. Eugene LeMay; Bruce E. Bursten; Catherine Murphy; Patrick Woodward; Matthew E. Stoltzfus
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Author: Theodore E. Brown; H. Eugene LeMay; Bruce E. Bursten; Catherine Murphy; Patrick Woodward; Matthew E. Stoltzfus
Publisher: Pearson
ISBN: 9780321910417
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Chapter: Problem: 1DE

Chemistry: The Central Science 13
Problem 1DE In this chapter we have seen that the reaction of potassium metal with oxygen leads to a product that we might not expect, namely, potassium superoxide, KO2(s). Lets design some experiments to learn more about this unusual product. (a) One of your team members proposes that the capacity

Chapter: Problem: 1E

Chemistry: The Central Science 13
As discussed in the text, we can draw an analogy between the attraction of an electron to a nucleus and the act of perceiving light from a lightbulbin essence, the more nuclear charge the electron sees, the greater the attraction. (a) Using this analogy, discuss how screening by core electrons is ana

Chapter: Problem: 2E

Chemistry: The Central Science 13
Which of these spheres represents \(F\), which represents \(B r\)-, and which represents \(B r\)-? [Section 7.3] Equation Transcription: Text Transcription: F Br Br

Chapter: Problem: 3E

Chemistry: The Central Science 13
Consider the \(\mathrm{Mg}^{2+}, \mathrm{Cl}^{-}, \mathrm{K}^{+}, \text {and } \mathrm{Se}^{2-}\) ions. The four spheres below represent these four ions, scaled according to ionic size. (a) Without referring to Figure 7.8, match each ion to its appropriate sphere. How do cations of the same charge

Chapter: Problem: 4E

Chemistry: The Central Science 13
In the following reaction which sphere represents a metal and which represents a nonmetal? Explain your answer. [Section 7.3]

Chapter: Problem: 6E

Chemistry: The Central Science 13
Shown below is a qualitative diagram of the atomic orbital energies for an Na atom. The number of orbitals in each subshell is not shown. (a) Are all of the subshells for \(n=1, n=2, \text { and } n=3\) shown? If not, what is missing? (b) The \(2 s \text { and } 2 p\) energy levels are sh

Chapter: Problem: 5E

Chemistry: The Central Science 13
Consider the \(A_{2} X_{4}\) molecule depicted here, where \(A \text { and } X\) are elements. The \(A \neg A\) bond length in this molecule is \(d 1\), and the four \(A-X\) bond lengths are each \(d_{2}\). (a) In terms of \(d_{1} \text { and } d_{2}\), how could you define the bonding atomic r

Chapter: Problem: 7E

Chemistry: The Central Science 13
(a) Which of the following charts below shows the general periodic trends for each of the following properties of the main-group elements (you can neglect small deviations going either across a row or down a column of the periodic table)? (1) Bonding atomic radius, (2) first ionization energy, and (3

Chapter: Problem: 9E

Chemistry: The Central Science 13
Problem 9E Periodic Table; Effective Nuclear Charge (Sections) (a) Evaluate the expressions 2x1,2x(1 +3), 2 x (1 + 3 + 5), and 2 x (1 + 3 + 5 + 7). (b) How do the atomic numbers of the noble gases relate to the numbers from part (a)? (c) What topic discussed in Chapter is the source of the number 2

Chapter: Problem: 8E

Chemistry: The Central Science 13
An element \(X\) reacts with F21g2 to form the molecular product shown here. (a) Write a balanced equation for this reaction (do not worry about the phases for \(X\) and the product). (b) Do you think that \(X\) is a metal or nonmetal? Explain. [Section 7.6]

Chapter: Problem: 11E

Chemistry: The Central Science 13
You might have expected that the elements would have been discovered in order of their relative abundance in the Earths crust (Figure 1.6), but this is not the case. Suggest a general reason. Relative abundances of elements.*Elements in percent by mass in Earths crust (including oceans and atmosphe

Chapter: Problem: 10E

Chemistry: The Central Science 13
The prefix eka- comes from the Sanskrit word for one. Mendeleev used this prefix to indicate that the unknown element was one place away from the known element that followed the prefix. For example, eka-silicon, which we now call germanium, is one element below silicon. Mendeleev also predicted the e

Chapter: Problem: 12E

Chemistry: The Central Science 13
Problem 12E Periodic Table; Effective Nuclear Charge (Sections) (a) Moseleys experiments on X rays emitted from atoms led to the concept of atomic numbers Where exactly do these X rayscome from? Draw an energy-level diagram to explain, (b) Why are chemical and physical properties of the elements mo

Chapter: Problem: 14E

Chemistry: The Central Science 13
Problem 14E Periodic Table; Effective Nuclear Charge (Sections) Which of the following statements about effective nuclear charge for the outermost valence electron of an atom is incorrect? (i) The effective nuclear charge can be thought of as the true nuclear charge minus a screening constant due t

Chapter: Problem: 13E

Chemistry: The Central Science 13
Problem 13E Periodic Table; Effective Nuclear Charge (Sections) (a) What is meant by the term effective nuclear charge? (b) How does the effective nuclear charge experienced by the valence electrons of an atom vary going from left to right across a period of the periodic table?

Chapter: Problem: 15E

Chemistry: The Central Science 13
Problem 15E Periodic Table; Effective Nuclear Charge (Sections) Detailed calculations show that the value of Zeff for the outermost electrons in Na and K atoms is 2.51+ and 3.49+, respectively, (a) What value do you estimate for Zeff experienced by the outermost electron in both Na and K by assumin

Chapter: Problem: 16E

Chemistry: The Central Science 13
Problem 16E Periodic Table; Effective Nuclear Charge (Sections) Detailed calculations show that the value of Zeff for the outermost electrons in Si and Cl atoms is 4.29+ and 6.12+, respectively, (a) What value do you estimate for Zeff experienced by the outermost electron in both Si and Cl by assum

Chapter: Problem: 17E

Chemistry: The Central Science 13
Problem 17E Periodic Table; Effective Nuclear Charge (Sections) Which will experience the greater effective nuclear charge, the electrons in the n = 3 shell in Ar or the n = 3 shell in Kr? Which will be closer to the nucleus?

Chapter: Problem: 18E

Chemistry: The Central Science 13
Problem 18E Periodic Table; Effective Nuclear Charge (Sections) Arrange the following atoms in order of increasing effective nuclear charge experienced by the electrons in the n = 3 electron shell: K. Mg. P. Rh. Ti.

Chapter: Problem: 19E

Chemistry: The Central Science 13
Problem 19E Atomic and Ionic Radii (Section) (a) Because an exact outer boundary cannot be measured or even calculated for an atom, how are atomic radii determined? (b) What is the difference between a bonding radius and a nonbonding radius? (c) For a given element, which one is larger? (d) If a fr

Chapter: Problem: 20E

Chemistry: The Central Science 13
Problem 20E Atomic and Ionic Radii (Section) (a) Why does the quantum mechanical description of manyelectron atoms make it difficult to define a precise atomic radius? (b) When nonbonded atoms come up against one another, what determines how closely the nuclear centers can approach?

Chapter: Problem: 22E

Chemistry: The Central Science 13
Problem 22E Which of the following statements about the bonding atomic radii in Figure is incorrect? (i) For a given period, the radii of the representative elements generally decrease from left to right across period, (ii) The radii of the representative elements for the n = 3 period are all large

Chapter: Problem: 21E

Chemistry: The Central Science 13
Problem 21E Atomic and Ionic Radii (Section) Tungsten has the highest melting point of any metal in the periodic table: 3422 C. The distance between W atoms in tungsten metal is 2.74 A. (a) What is the atomic radius of a tungsten atom in this environment? (This radius is called the metallic radius.

Chapter: Problem: 24E

Chemistry: The Central Science 13
The experimental \(B i-l\) bond length in bismuth triiodide, \(B i l_{3} \text { is } 2.81 \AA\). Based on this value and data in Figure 7.7, predict the atomic radius of \(B i\) Trends in bonding atomic radii for periods 1 through 5. Which part of the periodic table (top/bottom, left/right) has

Chapter: Problem: 26E

Chemistry: The Central Science 13
Problem 26E Atomic and Ionic Radii (Section) Using only the periodic table, arrange each set of atoms in order of increasing radius: (a) Ba, Ca. Na; (b) In. Sn. As; (c) Al. Be. Si.

Chapter: Problem: 23E

Chemistry: The Central Science 13
Estimate the \(A s-l\) bond length from the data in Figure 7.7 and compare your value to the experimental \(A s-l\) bond length in arsenic triiodide, \(A s l_{3}, 2.55 \AA\) Trends in bonding atomic radii for periods 1 through 5. Which part of the periodic table (top/bottom, left/right) has the e

Chapter: Problem: 25E

Chemistry: The Central Science 13
Problem 25E Atomic and Ionic Radii (Section) Using only the periodic table, arrange each set of atoms in order from largest to smallest: (a) K. Li, Cs; (b) Pb. Sn, Si; (c) F. O. N.

Chapter: Problem: 29E

Chemistry: The Central Science 13
Problem 29E Atomic and Ionic Radii (Section) Which neutral atom is isoelectronic with each of the following ions? Ga3+, Zr4+, Mn7+, I-, Pb2+.

Chapter: Problem: 27E

Chemistry: The Central Science 13
Problem 27E Atomic and Ionic Radii (Section) Identify each statement as true or false: (a) Cations are larger than their corresponding neutral atoms, (b) Li+ is smaller than Li. (c) Cl- is bigger than I-.

Chapter: Problem: 28E

Chemistry: The Central Science 13
Problem 28E Atomic and Ionic Radii (Section) Explain the following variations in atomic or ionic radii: (a) I- >1 >1+ (b) Ca2+ >Mg2+ >Be2+ (c) Fe >Fe2+ >Fe3+

Chapter: Problem: 30E

Chemistry: The Central Science 13
Problem 30E Atomic and Ionic Radii (Section) Some ions do not have a corresponding neutral atom that has the same electron configuration. For each of the following ions, identify the neutral atom that has the same number of electrons and determine if this atom has the same electron configuration. I

Chapter: Problem: 31E

Chemistry: The Central Science 13
Problem 31E Atomic and Ionic Radii (Section) Consider the isoelectronic ions F- and Na+. (a) Which ion is smaller? (b) Using Equation 7.1 and assuming that core electrons contribute 1.00 and valence electrons contribute 0.00 to the screening constant. S. calculate Zeff for the 2p electron

Chapter: Problem: 32E

Chemistry: The Central Science 13
Problem 32E Atomic and Ionic Radii (Section) Consider the isoelectronic ions Cl- and K+. (a) Which ion is smaller? (b) Using Equation and assuming that core electrons contribute 1.00 and valence electrons contribute nothing to the screening constant, S, calculate Zeff for these two ions, (c) Repeat

Chapter: Problem: 34E

Chemistry: The Central Science 13
Problem 34E Atomic and Ionic Radii (Section) Arrange each of the following sets of atoms and ions, in order of increasing size: (a) Se2-, Te2-, Se; (b) Co3+, Fe2+, Fe3+; (c) Ca. Ti4+, Sc3+; (d) Be2+, Na+, Ne.

Chapter: Problem: 33E

Chemistry: The Central Science 13
Problem 33E Atomic and Ionic Radii (Section) Consider S, Cl, and K and their most common ions, (a) List the atoms in order of increasing size, (b) List the ions in order of increasing size, (c) Explain any differences in the orders of the atomic and ionic sizes.

Chapter: Problem: 35E

Chemistry: The Central Science 13
Problem 35E Atomic and Ionic Radii (Section) Provide a brief explanation for each of the following: (a) 02-is larger than O. (b) S2- is larger than 02-. (c) S2- is larger than K+. (d) K+ is larger than Ca2+.

Chapter: Problem: 37E

Chemistry: The Central Science 13
Problem 37E Ionization Energies; Electron Affinities (Sections) Write equations that show the processes that describe the first, second, and third ionization energies of an aluminum atom. Which process would require the least amount of energy?

Chapter: Problem: 38E

Chemistry: The Central Science 13
Problem 38E Ionization Energies; Electron Affinities (Sections) Write equations that show the process for (a) the first two ionization energies of lead and (b) the fourth ionization energy of zirconium.

Chapter: Problem: 36E

Chemistry: The Central Science 13
In the ionic compounds \(\text { Lif, } \mathrm{NaCl}, \mathrm{KBr} \text {, and } \mathrm{Rbl}\), the measured cation-anion distances are \(2.01 \AA(L i-F), 2.82 \AA(N a-C l), 3.30 \AA(K-B r), \text { and } 3.67 \AA(R b-l)\), respectively. (a) Predict the cation-anion distance using the

Chapter: Problem: 39E

Chemistry: The Central Science 13
Problem 39E Ionization Energies; Electron Affinities (Sections) (a) Why does Li have a larger first ionization energy than Na? (b) The difference between the third and fourth ionization energies of scandium is much larger than that of titanium. Why? (c) Why does Li have a much larger second ionizat

Chapter: Problem: 41E

Chemistry: The Central Science 13
Problem 41E Ionization Energies; Electron Affinities (Sections) (a) What is the general relationship between the size of an atom and its first ionization energy? (b) Which element in the periodic table has the largest ionization energy? Which has the smallest?

Chapter: Problem: 40E

Chemistry: The Central Science 13
Problem 40E Ionization Energies; Electron Affinities (Sections) Identify each statement as true or false (a) Ionization energies are always negative quantities, (b) Oxygen has a larger first ionization energy than fluorine, (c) The second ionization energy of an atom is always greater than its

Chapter: Problem: 42E

Chemistry: The Central Science 13
Problem 42E Ionization Energies; Electron Affinities (Sections) (a) What is the trend in first ionization energies as one proceeds down the group 7 A elements? Explain how this trend relates to the variation in atomic radii, (b) What is the trend in first ionization energies as one moves across

Chapter: Problem: 43E

Chemistry: The Central Science 13
Problem 43E Ionization Energies; Electron Affinities (Sections) Based on their positions in the periodic table, predict which atom of the following pairs will have the smaller first ionization energy: (a) Cl. Ar; (b) Be. Ca; (c) K. Co; (d) S. Ge; (e) Sn. Te.

Chapter: Problem: 44E

Chemistry: The Central Science 13
Problem 44E Ionization Energies; Electron Affinities (Sections) For each of the following pairs, indicate which element has the smaller first ionization energy: (a) Ti, Ba: (b) Ag. Cu; (c) Ge, Cl; (d) Pb. Sb

Chapter: Problem: 45E

Chemistry: The Central Science 13
Problem 45E Ionization Energies; Electron Affinities (Sections) Write the electron configurations for the following ions, and determine which have noble-gas configurations: (a) Co2 +. (b) Sn2 +, (c) Zr4 +, (d) Ag+, (e) S2-.

Chapter: Problem: 46E

Chemistry: The Central Science 13
Problem 46E Ionization Energies; Electron Affinities (Sections) Write the electron configurations for the following ions, and determine which have noble-gas configurations: (a) Ru3 + , (b) As3 -, (c) Y3 + , (d) Pd2 + , (e) Pb2 + , (f) Au3 +.

Chapter: Problem: 47E

Chemistry: The Central Science 13
Problem 47E Ionization Energies; Electron Affinities (Sections) Find three examples of ions in the periodic table that have an electron configuration of ndS (n 3, 4, 5,c)

Chapter: Problem: 48E

Chemistry: The Central Science 13
Problem 48E Ionization Energies; Electron Affinities (Sections) Find three atoms in the periodic table whose ions have an electron configuration of nd6 (n = 3, 4, 5,c).

Chapter: Problem: 49E

Chemistry: The Central Science 13
Problem 49E Ionization Energies; Electron Affinities (Sections) The first ionization energy and electron affinity of Ar are both positive values, (a) What is the significance of the positive value in each case? (b) What are the units of electron affinity?

Chapter: Problem: 50E

Chemistry: The Central Science 13
Problem 50E Ionization Energies; Electron Affinities (Sections) f the electron affinity for an element is a negative number, does it mean that the anion of the element is more stable than the neutral atom? Explain.

Chapter: Problem: 51E

Chemistry: The Central Science 13
Problem 51E Ionization Energies; Electron Affinities (Sections) Although the electron affinity of bromine is a negative quantity, it is positive for Kr. Use the electron configurations of the two elements to explain the difference.

Chapter: Problem: 52E

Chemistry: The Central Science 13
Problem 52E Ionization Energies; Electron Affinities (Sections) What is the relationship between the ionization energy of an anion with a 1- charge such as F-and the electron affinity of the neutral atom. F?

Chapter: Problem: 53E

Chemistry: The Central Science 13
Problem 53E Ionization Energies; Electron Affinities (Sections) Consider the first ionization energy of neon and the electron affinity of fluorine, (a) Write equations, including electron configurations, for each process, (b) These two quantities have opposite signs. Which will be positive, and whi

Chapter: Problem: 54E

Chemistry: The Central Science 13
Problem 54E Ionization Energies; Electron Affinities (Sections) Consider the following equation; Ca+(gj + eCa (g) Which of the following statements are true? (i) The energy change for this process is the electron affinity of the Ca+ ion. (ii) The energy change for this process is the negative o

Chapter: Problem: 55E

Chemistry: The Central Science 13
Problem 55E Properties of Metals and Nonmetals (Section) (a) Does metallic character increase, decrease, or remain unchanged as one goes from left to right across a row of the periodic table? (b) Does metallic character increase, decrease, or remain unchanged as one goes down a column of the period

Chapter: Problem: 56E

Chemistry: The Central Science 13
Problem 56E Properties of Metals and Nonmetals (Section) You read the following statement about two elements X and Y: One of the elements is a good conductor of electricity, and the other is a semiconductor. Experiments show that the first ionization energy of X is twice as great as that of Y. Whic

Chapter: Problem: 57E

Chemistry: The Central Science 13
Problem 57E Properties of Metals and Nonmetals (Section) You read the following statement about two elements X and Y: One of the elements is a good conductor of electricity, and the other is a semiconductor. Experiments show that the first ionization energy of X is twice as great as that of Y. Whic

Chapter: Problem: 59E

Chemistry: The Central Science 13
Problem 59E Properties of Metals and Nonmetals (Section) Discussing this chapter, a classmate says, "Since elements that form cations are metals and elements that form anions are nonmetals, elements that do not form ions are metalloids." Do you agree or disagree? Explain your answer

Chapter: Problem: 58E

Chemistry: The Central Science 13
Problem 58E Properties of Metals and Nonmetals (Section) Discussing this chapter, a classmate says, "An element that commonly forms a cation is a metal." Do you agree or disagree? Explain your answer

Chapter: Problem: 61E

Chemistry: The Central Science 13
Problem 61E Properties of Metals and Nonmetals (Section) Some metal oxides, such as Sc203. do not react with pure water, but they do react when the solution becomes either acidic or basic. Do you expect Sc203 to react when the solution becomes acidic or when it becomes basic? Write a balanced chemi

Chapter: Problem: 62E

Chemistry: The Central Science 13
Problem 62E Properties of Metals and Nonmetals (Section) (a) What is meant by the terms acidic oxide and basic oxide? (b) How can we predict whether an oxide will be acidic or basic based on its composition?

Chapter: Problem: 60E

Chemistry: The Central Science 13
Problem 60E Properties of Metals and Nonmetals (Section) Predict whether each of the following oxides is ionic or molecular: Sn02. AI203, C02. Li20. Fe203, H20.

Chapter: Problem: 63E

Chemistry: The Central Science 13
Problem 63E Properties of Metals and Nonmetals (Section) Arrange the following oxides in order of increasing acidity: C02. CaO. AI203, S03, Si02. P205.

Chapter: Problem: 64E

Chemistry: The Central Science 13
An element \(\mathrm{X}\) reacts with oxygen to form \(\mathrm{XO}_{2}\) and with chlorine to form \(\mathrm{XCl}_{4}, \mathrm{XO}_{2}\) is a white solid that melts at high temperatures (above \(1000^{\circ} \mathrm{C}\)). Under usual conditions, \(\mathrm{XCl}_{4}\) is a colorless liquid with a boil

Chapter: Problem: 65E

Chemistry: The Central Science 13
Problem 65E Properties of Metals and Nonmetals (Section) An element X reacts with oxygen to form X02 and with chlorine to form XCI4. X02 is a white solid that melts at high temperatures (above 1000 C). Under usual conditions, XCI4 is a colorless liquid with a boiling point of 58 C. (a) XCI4 reacts

Chapter: Problem: 66E

Chemistry: The Central Science 13
Problem 66E Properties of Metals and Nonmetals (Section) Write balanced equations for the following reactions: (a) barium oxide with water, (b) iron(ll) oxide with perchloric acid, (c) sulfur trioxide with water, (d) carbon dioxide with aqueous sodium hydroxide.

Chapter: Problem: 69E

Chemistry: The Central Science 13
Problem 69E Group Trends in Metals and Nonmetals (Sections) Write a balanced equation for the reaction that occurs in each of the following cases: (a) Potassium metal is exposed to an atmosphere of chlorine gas. (b) Strontium oxide is added to water, (c) A fresh surface of lithium metal is exposed

Chapter: Problem: 67E

Chemistry: The Central Science 13
Problem 67E Group Trends in Metals and Nonmetals (Sections) (a) Why is calcium generally more reactive than magnesium? (b) Why is calcium generally less reactive than potassium?

Chapter: Problem: 68E

Chemistry: The Central Science 13
Problem 68E Group Trends in Metals and Nonmetals (Sections) Silver and rubidium both form +1 ions, but silver is far less reactive. Suggest an explanation, taking into account the ground-state electron configurations of these elements and their atomic radii.

Chapter: Problem: 70E

Chemistry: The Central Science 13
Problem 70E Group Trends in Metals and Nonmetals (Sections) Write a balanced equation for the reaction that occurs in each of the following cases: (a) Cesium is added to water, (b) Strontium is added to water, (c) Sodium reacts with oxygen, (d) Calcium reacts with iodine.

Chapter: Problem: 71E

Chemistry: The Central Science 13
Problem 71E Group Trends in Metals and Nonmetals (Sections) (a) As described in Section, the alkali metals react with hydrogen to form hydrides and react with halogens to form halides. Compare the roles of hydrogen and halogens in these reactions. How are the forms of hydrogen and halogens in the p

Chapter: Problem: 72E

Chemistry: The Central Science 13
Potassium and hydrogen react to form the ionic compound potassium hydride. (a) Write a balanced equation for this reaction. (b) Use data in Figures 7.10 and 7.12 to determine the energy change in kJ/mol for the following two reactions: \(K(g)+H(g) \rightarrow K^{+}(g)+H^{-}(g)\) \(K(g)+H

Chapter: Problem: 73E

Chemistry: The Central Science 13
Problem 73E Group Trends in Metals and Nonmetals (Sections) Compare the elements bromine and chlorine with respect to the following properties: (a) electron configuration, (b) mostcommon ionic charge, (c) first ionization energy, (d) reactivity toward water, (e) electron affinity, (f) atomic radius

Chapter: Problem: 74E

Chemistry: The Central Science 13
Problem 74E Group Trends in Metals and Nonmetals (Sections) Little is known about the properties of astatine, At, because of its rarity and high radioactivity. Nevertheless, it is possible for us to make many predictions about its properties. (a) Doyou expect the element to be a gas, liquid, or sol

Chapter: Problem: 76E

Chemistry: The Central Science 13
Problem 76E Group Trends in Metals and Nonmetals (Sections) (a) Why does xenon react with fluorine, whereas neon does not? (b) Using appropriate reference sources, look up the bond lengths of XeF bonds in several molecules. How do these numbers compare to the bond lengths calculated from the atomic

Chapter: Problem: 75E

Chemistry: The Central Science 13
Problem 75E Group Trends in Metals and Nonmetals (Sections) Until the early 1960s the group 8A elements were called the inert gases. (a) Why was the term inert gases dropped? (b) What discovery triggered this change in name? (c) What name is applied to the group now?

Chapter: Problem: 77E

Chemistry: The Central Science 13
Problem 77E Group Trends in Metals and Nonmetals (Sections) Write a balanced equation for the reaction that occurs in each of the following cases: (a) Ozone decomposes to dioxygen. (b) Xenon reacts with fluorine. (Write three different equations.) (c) Sulfur reacts with hydrogen gas. (d) Fluorine r

Chapter: Problem: 80AE

Chemistry: The Central Science 13
Figure 7.4 shows the radial probability distribution functions for the \(2 s\) orbitals and \(2 p\) orbitals. (a) Which orbital, \(2 s \text { or } 2 p\), has more electron density close to the nucleus? (b) How would you modify Slaters rules to adjust for the difference in electronic pene

Chapter: Problem: 81AE

Chemistry: The Central Science 13
Problem 81AE (a) If the core electrons were totally effective at screening the valence electrons and the valence electrons provided no screening for each other, what would be the effective nuclear charge acting on the 3s and 3p valence electrons in P? (b) Repeat these calculations using Slaters rul

Chapter: Problem: 78E

Chemistry: The Central Science 13
Problem 78E Group Trends in Metals and Nonmetals (Sections) Write a balanced equation for the reaction that occurs in each of the following cases:(a) Chlorine reacts with water. (b) Barium metal is heated in an atmosphere of hydrogen gas. (c) Lithium reacts with sulfur. (d) Fluorine reacts with ma

Chapter: Problem: 79AE

Chemistry: The Central Science 13
Problem 79AE Consider the stable elements through lead (Z = 82). In how many instances are the atomic weights of the elements out of order relative to the atomic numbers of the elements?

Chapter: Problem: 82AE

Chemistry: The Central Science 13
Problem 82AE As we move across a period of the periodic table, why do the sizes of the transition elements change more gradually than those of the representative elements?

Chapter: Problem: 83AE

Chemistry: The Central Science 13
In the series of group 5A hydrides, of general formula \(M H_{3}\), the measured bond distances are \(P-H, 1.1419 \AA \text { A } ; A s-H, 1.519 \AA \text {; } S b-H, 1.707 \AA\) (a) Compare these values with those estimated by use of the atomic radii in Figure 7.7. (b) Explain the steady incre

Chapter: Problem: 84AE

Chemistry: The Central Science 13
Problem 84AE In Table the bonding atomic radius of neon is listed as 0.58 , whereas that for xenon is listed as 1.40 . A classmate of yours states that the value for Xe is more realistic than the one for Ne. Is she correct? If so, what is the basis for her statement? Table Some Properties of the

Chapter: Problem: 87AE

Chemistry: The Central Science 13
Problem 87AE Elements in group 7 A in the periodic table are called the halogens; elements in group 6A are called the chalcogens (a) What is the most common oxidation state of the chalcogens compared to the halogens? (b) For each of the following periodic properties, state whether the halogens or t

Chapter: Problem: 85AE

Chemistry: The Central Science 13
The \(\mathrm{As}-\mathrm{As}\) bond length in elemental arsenic is \(2.48 \AA\). The \(\mathrm{Cl}-\mathrm{Cl}\) bond length in \(\mathrm{Cl}_{2} \text { is } 1.99 \AA\). (a) Based on these data, what is the predicted \(\mathrm{As}-\mathrm{Cl}\) bond length in arsenic trichloride, \(\mathrm{AsCl

Chapter: Problem: 86AE

Chemistry: The Central Science 13
Problem 86AE The following observations are made about two hypothetical elements A and B: The AA and BB bond lengths in elemental A and B are 2.36 and 1.94 A. respectively. A and B react to form the binary compound AB2. which has a linear structure (that is^B-A-B = 180). Based on these statements,

Chapter: Problem: 88AE

Chemistry: The Central Science 13
Note from the following table that there is a significant increase in atomic radius upon moving from \(Y\) to La whereas the radii of \(\mathrm{Zr}$ to $\mathrm{Hf}\) are the same. Suggest an explanation for this effect. Equation Transcription: Text Tran

Chapter: Problem: 89AE

Chemistry: The Central Science 13
Problem 89AE (a) Which ion is smaller, Co3+ or Co+? (b) In a lithium-ion battery that is discharging to power a device, for every Li+ that inserts into the lithium cobalt oxide electrode, a Co4+ ion must be reduced to a Co3+ ion to balance charge. Using the CRCHandbook of Chemistry and Physics or o

Chapter: Problem: 90AE

Chemistry: The Central Science 13
The ionic substance strontium oxide, \(\mathrm{SrO}\), forms from the reaction of strontium metal with molecular oxygen. The arrangement of the ions in solid \(\mathrm{SrO}\) is analogous to that in solid \(\mathrm{NaCl}\): (a) Write a balanced equation for the formation of \(\mathrm{SrO}(\ma

Chapter: Problem: 92AE

Chemistry: The Central Science 13
Group 4A elements have much more negative electron affinities than their neighbors in groups 3A and 5A (see Figure 7.12). Which of the following statements best explains this observation? (i) The group 4A elements have much higher first ionization energies than their neighbors in groups 3A and 5A.

Chapter: Problem: 91AE

Chemistry: The Central Science 13
Explain the variation in the ionization energies of carbon, as displayed in this graph:

Chapter: Problem: 94AE

Chemistry: The Central Science 13
Problem 94AE (a) Use orbital diagrams to illustrate what happens when an oxygen atom gains two electrons. (b) Why does 03 - not exist?

Chapter: Problem: 93AE

Chemistry: The Central Science 13
Problem 93AE In the chemical process called electron transfer, an electron is transferred from one atom or molecule to another. (We will talk about electron transfer extensively in Chapter) A simple electron transfer reaction is A (g) + A(g)-*A+(g) + A -(g) In terms of the ionization energy and

Chapter: Problem: 96AE

Chemistry: The Central Science 13
Problem 96AE Identify two ions that have the following ground-state electron configurations: (a) [Ar], (b) [Ar]3d5, (c) [Kr]5s24c(10

Chapter: Problem: 95AE

Chemistry: The Central Science 13
Problem 95AE Use electron configurations to explain the following observations: (a) The first ionization energy of phosphorus is greater than that of sulfur (b) The electron affinity of nitrogen is lower (less negative) than those of both carbon and oxygen, (c) The second ionization energy of oxyge

Chapter: Problem: 97AE

Chemistry: The Central Science 13
Problem 97AE Which of the following chemical equations is connected to the definitions of (a) the first ionization energy of oxygen, (b) the second ionization energy of oxygen, (c) the electron affinity of oxygen? (i) O(g) + e-?O-(g) (ii) O(g)?O+(g) + e- (iii) O(g)+ 2e-?O2-(g) (iv) O(g)?O2+(g) + 2e

Chapter: Problem: 98AE

Chemistry: The Central Science 13
The electron affinities, in \(\mathrm{kJ} / \mathrm{mol}\), for the group 1B and group 2B metals are as follows: (a) Why are the electron affinities of the group 2B elements greater than zero? (b) Why do the electron affinities of the group 1B elements become more negative as we move down the

Chapter: Problem: 99AE

Chemistry: The Central Science 13
Problem 99AE Hydrogen is an unusual element because it behaves in some ways like the alkali metal elements and in other ways like nonmetals. Its properties can be explained in part by its electron configuration and by the values for its ionization energy and electron affinity, (a) Explain why the e

Chapter: Problem: 100AE

Chemistry: The Central Science 13
Problem 100AE The first ionization energy of the oxygen molecule is the energy required for the following process: 02(g)>02+(g) + e- The energy needed for this process is 1175 kJ/mol, very similarto the first ionization energy of Xe. Would you expect 02 to react with F2? If so. suggest a produc

Chapter: Problem: 101AE

Chemistry: The Central Science 13
Problem 101AE It is possible to define metallic character as we do in this book and base it on the reactivity of the element and the ease with which it loses electrons. Alternatively, one could measure how well electricity is conducted by each of the elements to determine how metallic" the elements

Chapter: Problem: 102AE

Chemistry: The Central Science 13
Problem 102AE Which of the following is the expected product of the reaction of K(s) and H2(g)? (i) KH(s), (ii) K2H(s), (iii) KH2(s), (iv) K2H2(s), or (v) K(s) and H2(g) will not react with one another

Chapter: Problem: 103AE

Chemistry: The Central Science 13
Problem 103AE Elemental cesium reacts more violently with water than does elemental sodium. Which of the following best explains this difference in reactivity? (i) Sodium has greater metallic character than does cesium, (ii) The first ionization energy of cesium is less than that of sodium, (iii) T

Chapter: Problem: 104AE

Chemistry: The Central Science 13
Problem 104AE (a) One of the alkali metals reacts with oxygen to form a solid white substance. When this substance is dissolved in water, the solution gives a positive test for hydrogen peroxide. H202. When the solution is tested in a burner flame, a lilac-purple flame is produced. What is the like

Chapter: Problem: 105AE

Chemistry: The Central Science 13
Problem 105AE Zinc in its 2+ oxidation state is an essential metal ion for life. Zn2+ is found bound to many proteins that are involved in biological processes, but unfortunately Zn2+ is hard to detect by common chemical methods. Therefore, scientists who are interested in studying Zn2+-containing

Chapter: Problem: 106AE

Chemistry: The Central Science 13
A historian discovers a nineteenth-century notebook in which some observations, dated 1822, were recorded on a substance thought to be a new element. Here are some of the data recorded in the notebook: Ductile, silver-white, metallic looking. Softer than lead. Unaffected by water. Stable in air. Melt

Chapter: Problem: 108AE

Chemistry: The Central Science 13
Problem 108AE We will see in Chapter that semiconductors are materials that conduct electricity better than nonmetals but not as well as metals. The only two elements in the periodic table that are technologically useful semiconductors are silicon and germanium. Integrated circuits in computer chip

Chapter: Problem: 107AE

Chemistry: The Central Science 13
Problem 107AE In April 2010, a research team reported that it had made Element 117. This discovery was confirmed in 2012 by additional experiments. Write the ground-state electron configuration for Element 117 and estimate values for its first ionization energy, electron affinity, atomic size, and

Chapter: Problem: 109IE

Chemistry: The Central Science 13
Moseley established the concept of atomic number by studying X rays emitted by the elements. The X rays emitted by some of the elements have the following wavelengths: (a) Calculate the frequency, \(v\), of the X rays emitted by each of the elements, in Hz. (b) Plot the square root of vers

Chapter: Problem: 110IE

Chemistry: The Central Science 13
(a) Write the electron configuration for \(L i \) and estimate the effective nuclear charge experienced by the valence electron. (b) The energy of an electron in a one-electron atom or ion equals \(\left(-2.18 \times 10^{-18} J\right)\left(\frac{Z^{2}}{n^{2}}\right)\), where Z is the nuclear

Chapter: Problem: 111IE

Chemistry: The Central Science 13
One way to measure ionization energies is ultraviolet photoelectron spectroscopy (PES), a technique based on the photoelectric effect. (Section 6.2) In PES, monochromatic light is directed onto a sample, causing electrons to be emitted. The kinetic energy of the emitted electrons is measured. The

Chapter: Problem: 112IE

Chemistry: The Central Science 13
Problem 112IE Mercury in the environment can exist in oxidation states 0, +1, and +2. One major question in environmental chemistry research is how to best measure the oxidation state of mercury in natural systems; this is made more complicated by the fact that mercury can be reduced or oxidized on

Chapter: Problem: 114IE

Chemistry: The Central Science 13
(a) The measured \(\mathrm{Bi} \neg \mathrm{Br}\) bond length in bismuth tribromide, \(\mathrm{BiBr}_{3} \text {, is } 2.63 \AA\). Based on this value and the data in Figure 7.8, predict the atomic radius of \(\mathrm{Bi}\). (b) Bismuth tribromide is soluble in acidic solution. It is formed by tre

Chapter: Problem: 113IE

Chemistry: The Central Science 13
When magnesium metal is burned in air (Figure 3.6), two products are produced. One is magnesium oxide, \(\mathrm{MgO}\). The other is the product of the reaction of Mg with molecular nitrogen, magnesium nitride. When water is added to magnesium nitride, it reacts to form magnesium oxide and ammonia g

Chapter: Problem: 115IE

Chemistry: The Central Science 13
Problem 115IE Potassium superoxide. K02, is often used in oxygen masks (such as those used by firefighters) because K02 reacts with C02 to release molecular oxygen. Experiments indicate that 2 mol of K02(s) react with each mole of 002(g). (a) The products of the reaction are K2C03(s) and 02(g). Wri

Chapter: Problem: 7.1

Chemistry: The Central Science 13
As discussed in the text, we can draw an analogy between the attraction of an electron to a nucleus and the act of perceiving light from a lightbulbin essence, the more nuclear charge the electron sees, the greater the attraction. (a) Using this analogy, discuss how screening by core electrons is ana

Chapter: Problem: 7.2

Chemistry: The Central Science 13
Which of these spheres represents F, which represents Br, and which represents Br -? [Section 7.3]

Chapter: Problem: 7.3

Chemistry: The Central Science 13
Consider the Mg2+, Cl -, K+, and Se 2- ions. The four spheres below represent these four ions, scaled according to ionic size. (a) Without referring to Figure 7.8, match each ion to its appropriate sphere. (b) In terms of size, between which of the spheres would you find the (i) Ca 2 + and (ii) S2 -

Chapter: Problem: 7.4

Chemistry: The Central Science 13
In the following reaction Reactants Products which sphere represents a metal and which represents a nonmetal? Explain your answer. [Section 7.3]

Chapter: Problem: 7.5

Chemistry: The Central Science 13
Consider the A2X4 molecule depicted here, where A and X are elements. The AA bond length in this molecule is d1, and the four AX bond lengths are each d2. (a) In terms of d1 and d2, how could you define the bonding atomic radii of atoms A and X? (b) In terms of d1 and d2, what would you predict for t

Chapter: Problem: 7.6

Chemistry: The Central Science 13
Shown below is a qualitative diagram of the atomic orbital energies for an Na atom. The number of orbitals in each subshell is not shown. 2p 3p 3s 2s 1s E (a) Are all of the subshells for n = 1, n = 2, and n = 3 shown? If not, what is missing? (b) The 2s and 2p energy levels are shown as different. W

Chapter: Problem: 7.7a

Chemistry: The Central Science 13
(a) Which of the following charts below shows the general periodic trends for each of the following properties of the main-group elements (you can neglect small deviations going either across a row or down a column of the periodic table)? (1) Bonding atomic radius, (2) first ionization energy, and(3)

Chapter: Problem: 7.7b

Chemistry: The Central Science 13
(b) Do any of the charts show the general periodic trends in the electron affinities of the maingroup elements? [Sections 7.27.6]

Chapter: Problem: 7.8

Chemistry: The Central Science 13
An element X reacts with F21g2 to form the molecular product shown here. (a) Write a balanced equation for this reaction (do not worry about the phases for X and the product). (b) Do you think that X is a metal or nonmetal? Explain. [Section 7.6] F X F F F

Chapter: Problem: 7.9a

Chemistry: The Central Science 13
( a ) Evaluate the expressions 2 * 1, 2 * 11 + 32, 2 * 11 + 3 + 52, and 2 * 11 + 3 + 5 + 72

Chapter: Problem: 7.9b

Chemistry: The Central Science 13
(b) How do the atomic numbers of the noble gases relate to the numbers from part (a)? (c) What topic discussed in Chapter 6 is the source of the number 2 in the expressions in part (a)?

Chapter: Problem: 7.10

Chemistry: The Central Science 13
The prefix eka- comes from the Sanskrit word for one. Mendeleev used this prefix to indicate that the unknown element was one place away from the known element that followed the prefix. For example, eka-silicon, which we now call germanium, is one element below silicon. Mendeleev also predicted the e

Chapter: Problem: 7.11

Chemistry: The Central Science 13
You might have expected that the elements would have been discovered in order of their relative abundance in the Earths crust (Figure 1.6), but this is not the case. Suggest a general reason.

Chapter: Problem: 7.12a

Chemistry: The Central Science 13
(a) Moseleys experiments on X rays emitted from atoms led to the concept of atomic numbers. Where exactly do these X rays come from? Draw an energy-level diagram to explain

Chapter: Problem: 7.12b

Chemistry: The Central Science 13
(b) Why are chemical and physical properties of the elements more closely related to atomic numbers than they are to atomic weights?

Chapter: Problem: 7.13a

Chemistry: The Central Science 13
(a) What is meant by the term effective nuclear charge?

Chapter: Problem: 7.13b

Chemistry: The Central Science 13
(b) How does the effective nuclear charge experienced by the valence electrons of an atom vary going from left to right across a period of the periodic table?

Chapter: Problem: 7.14

Chemistry: The Central Science 13
Which of the following statements about effective nuclear charge for the outermost valence electron of an atom is incorrect? (i) The effective nuclear charge can be thought of as the true nuclear charge minus a screening constant due to the other electrons in the atom. (ii) Effective nuclear charge i

Chapter: Problem: 7.15

Chemistry: The Central Science 13
Detailed calculations show that the value of Zeff for the outermost electrons in Na and K atoms is 2.51+ and 3.49+, respectively. (a) What value do you estimate for Zeff experienced by the outermost electron in both Na and K by assuming core electrons contribute 1.00 and valence electrons contribute

Chapter: Problem: 7.16

Chemistry: The Central Science 13
Detailed calculations show that the value of Zeff for the outermost electrons in Si and Cl atoms is 4.29+ and 6.12+, respectively. (a) What value do you estimate for Zeff experienced by the outermost electron in both Si and Cl by assuming core electrons contribute 1.00 and valence electrons contribut

Chapter: Problem: 7.17

Chemistry: The Central Science 13
Which will experience the greater effective nuclear charge, the electrons in the n = 3 shell in Ar or the n = 3 shell in Kr? Which will be closer to the nucleus?

Chapter: Problem: 7.18

Chemistry: The Central Science 13
Arrange the following atoms in order of increasing effective nuclear charge experienced by the electrons in the n = 3 electron shell: K, Mg, P, Rh, Ti.

Chapter: Problem: 7.19a

Chemistry: The Central Science 13
(a) Because an exact outer boundary cannot be measured or even calculated for an atom, how are atomic radii determined?

Chapter: Problem: 7.19b

Chemistry: The Central Science 13
(b) What is the difference between a bonding radius and a nonbonding radius?

Chapter: Problem: 7.19c

Chemistry: The Central Science 13
(c) For a given element, which one is larger?

Chapter: Problem: 7.19d

Chemistry: The Central Science 13
(d) If a free atom reacts to become part of a molecule, would you say that the atom gets smaller or larger?

Chapter: Problem: 7.20a

Chemistry: The Central Science 13
(a) Why does the quantum mechanical description of manyelectron atoms make it difficult to define a precise atomic radius?

Chapter: Problem: 7.20b

Chemistry: The Central Science 13
(b) When nonbonded atoms come up against one another, what determines how closely the nuclear centers can approach?

Chapter: Problem: 7.21

Chemistry: The Central Science 13
Tungsten has the highest melting point of any metal in the periodic table: 3422 C. The distance between W atoms in tungsten metal is 2.74 . (a) What is the atomic radius of a tungsten atom in this environment? (This radius is called the metallic radius.) (b) If you put tungsten metal under high press

Chapter: Problem: 7.22

Chemistry: The Central Science 13
Which of the following statements about the bonding atomic radii in Figure 7.7 is incorrect? (i) For a given period, the radii of the representative elements generally decrease from left to right across period. (ii) The radii of the representative elements for the n = 3 period are all larger than tho

Chapter: Problem: 7.23

Chemistry: The Central Science 13
Estimate the AsI bond length from the data in Figure 7.7 and compare your value to the experimental AsI bond length in arsenic triiodide, AsI3, 2.55 .

Chapter: Problem: 7.24

Chemistry: The Central Science 13
The experimental BiI bond length in bismuth triiodide, BiI3, is 2.81 . Based on this value and data in Figure 7.7, predict the atomic radius of Bi.

Chapter: Problem: 7.25

Chemistry: The Central Science 13
Using only the periodic table, arrange each set of atoms in order from largest to smallest: (a) K, Li, Cs; (b) Pb, Sn, Si; (c) F, O, N.

Chapter: Problem: 7.26

Chemistry: The Central Science 13
Using only the periodic table, arrange each set of atoms in order of increasing radius: (a) Ba, Ca, Na; (b) In, Sn, As; (c) Al, Be, Si

Chapter: Problem: 7.27

Chemistry: The Central Science 13
Identify each statement as true or false: (a) Cations are larger than their corresponding neutral atoms. (b) Li + is smaller than Li. (c) Cl - is bigger than I -.

Chapter: Problem: 7.28

Chemistry: The Central Science 13
Explain the following variations in atomic or ionic radii: (a) I - 7 I 7 I + (b) Ca 2+ 7 Mg2+ 7 Be 2+ (c) Fe 7 Fe 2+ 7 Fe 3+

Chapter: Problem: 7.29

Chemistry: The Central Science 13
Which neutral atom is isoelectronic with each of the following ions? Ga 3+, Zr 4+, Mn7+, I -, Pb2+.

Chapter: Problem: 7.30

Chemistry: The Central Science 13
Some ions do not have a corresponding neutral atom that has the same electron configuration. For each of the following ions, identify the neutral atom that has the same number of electrons and determine if this atom has the same electron configuration. If such an atom does not exist, explain why. (a)

Chapter: Problem: 7.31

Chemistry: The Central Science 13
Consider the isoelectronic ions F- and Na +. (a) Which ion is smaller? (b) Using Equation 7.1 and assuming that core electrons contribute 1.00 and valence electrons contribute 0.00 to the screening constant, S, calculate Zeff for the 2p electrons in both ions. (c) Repeat this calculation using Slater

Chapter: Problem: 7.32

Chemistry: The Central Science 13
Consider the isoelectronic ions Cl - and K+. (a) Which ion is smaller? (b) Using Equation 7.1 and assuming that core electrons contribute 1.00 and valence electrons contribute nothing to the screening constant, S, calculate Zeff for these two ions. (c) Repeat this calculation using Slaters rules to e

Chapter: Problem: 7.33

Chemistry: The Central Science 13
Consider S, Cl, and K and their most common ions. (a) List the atoms in order of increasing size. (b) List the ions in order of increasing size. (c) Explain any differences in the orders of the atomic and ionic sizes.

Chapter: Problem: 7.34

Chemistry: The Central Science 13
Arrange each of the following sets of atoms and ions, in order of increasing size: (a) Se 2-, Te 2-, Se; (b) Co3+, Fe 2+, Fe 3+; (c) Ca, Ti 4+, Sc3+; (d) Be 2+, Na +, Ne.

Chapter: Problem: 7.35

Chemistry: The Central Science 13
Provide a brief explanation for each of the following: (a) O2- is larger than O. (b) S2- is larger than O2- . (c) S2- is larger than K+. (d) K+ is larger than Ca 2+

Chapter: Problem: 7.36

Chemistry: The Central Science 13
In the ionic compounds LiF, NaCl, KBr, and RbI, the measured cationanion distances are 2.01 (LiF), 2.82 (NaCl), 3.30 (KBr), and 3.67 (RbI), respectively. (a) Predict the cationanion distance using the values of ionic radii given in Figure 7.8. (b) Calculate the difference between the experimentally m

Chapter: Problem: 7.37

Chemistry: The Central Science 13
Write equations that show the processes that describe the first, second, and third ionization energies of an aluminum atom. Which process would require the least amount of energy?

Chapter: Problem: 7.38

Chemistry: The Central Science 13
Write equations that show the process for (a) the first two ionization energies of lead and (b) the fourth ionization energy of zirconium.

Chapter: Problem: 7.39a

Chemistry: The Central Science 13
(a) Why does Li have a larger first ionization energy than Na?

Chapter: Problem: 7.39b

Chemistry: The Central Science 13
(b) The difference between the third and fourth ionization energies of scandium is much larger than that of titanium. Why? (c) Why does Li have a much larger second ionization energy than Be?

Chapter: Problem: 7.40

Chemistry: The Central Science 13
Identify each statement as true or false: (a) Ionization energies are always negative quantities. (b) Oxygen has a larger first ionization energy than fluorine. (c) The second ionization energy of an atom is always greater than its first ionization energy. (d) The third ionization energy is the energ

Chapter: Problem: 7.41a

Chemistry: The Central Science 13
(a) What is the general relationship between the size of an atom and its first ionization energy?

Chapter: Problem: 7.41b

Chemistry: The Central Science 13
(b) Which element in the periodic table has the largest ionization energy? Which has the smallest?

Chapter: Problem: 7.42a

Chemistry: The Central Science 13
(a) What is the trend in first ionization energies as one proceeds down the group 7A elements? Explain how this trend relates to the variation in atomic radii

Chapter: Problem: 7.42b

Chemistry: The Central Science 13
(b) What is the trend in first ionization energies as one moves across the fourth period from K to Kr? How does this trend compare with the trend in atomic radii?

Chapter: Problem: 7.43

Chemistry: The Central Science 13
Based on their positions in the periodic table, predict which atom of the following pairs will have the smaller first ionization energy: (a) Cl, Ar; (b) Be, Ca; (c) K, Co; (d) S, Ge; (e) Sn, Te.

Chapter: Problem: 7.44

Chemistry: The Central Science 13
For each of the following pairs, indicate which element has the smaller first ionization energy: (a) Ti, Ba; (b) Ag, Cu; (c) Ge, Cl; (d) Pb, Sb.

Chapter: Problem: 7.45

Chemistry: The Central Science 13
Write the electron configurations for the following ions, and determine which have noble-gas configurations: (a) Co2 + , (b) Sn2 + , (c) Zr 4 + , (d) Ag+, (e) S2 - .

Chapter: Problem: 7.46

Chemistry: The Central Science 13
Write the electron configurations for the following ions, and determine which have noble-gas configurations: (a) Ru3 + , (b) As 3 - , (c) Y3 + , (d) Pd2 + , (e) Pb2 + , (f) Au3 + .

Chapter: Problem: 7.47

Chemistry: The Central Science 13
Find three examples of ions in the periodic table that have an electron configuration of nd8 1n = 3, 4, 5, c2.

Chapter: Problem: 7.48

Chemistry: The Central Science 13
Find three atoms in the periodic table whose ions have an electron configuration of nd6 1n = 3, 4, 5, c2.

Chapter: Problem: 7.49

Chemistry: The Central Science 13
The first ionization energy and electron affinity of Ar are both positive values. (a) What is the significance of the positive value in each case? (b) What are the units of electron affinity?

Chapter: Problem: 7.50

Chemistry: The Central Science 13
If the electron affinity for an element is a negative number, does it mean that the anion of the element is more stable than the neutral atom? Explain.

Chapter: Problem: 7.51

Chemistry: The Central Science 13
Although the electron affinity of bromine is a negative quantity, it is positive for Kr. Use the electron configurations of the two elements to explain the difference

Chapter: Problem: 7.52

Chemistry: The Central Science 13
What is the relationship between the ionization energy of an anion with a 1- charge such as F- and the electron affinity of the neutral atom, F?

Chapter: Problem: 7.53

Chemistry: The Central Science 13
Consider the first ionization energy of neon and the electron affinity of fluorine. (a) Write equations, including electron configurations, for each process. (b) These two quantities have opposite signs. Which will be positive, and which will be negative? (c) Would you expect the magnitudes of these

Chapter: Problem: 7.54

Chemistry: The Central Science 13
Consider the following equation: Ca +1g2 + e- Ca1g2 Which of the following statements are true? (i) The energy change for this process is the electron affinity of the Ca + ion. (ii) The energy change for this process is the negative of the first ionization energy of the Ca atom. (iii) The energy chan

Chapter: Problem: 7.55a

Chemistry: The Central Science 13
(a) Does metallic character increase, decrease, or remain unchanged as one goes from left to right across a row of the periodic table?

Chapter: Problem: 7.55b

Chemistry: The Central Science 13
(b) Does metallic character increase, decrease, or remain unchanged as one goes down a column of the periodic table?

Chapter: Problem: 7.55c

Chemistry: The Central Science 13
(c) Are the periodic trends in (a) and (b) the same as or different from those for first ionization energy?

Chapter: Problem: 7.56

Chemistry: The Central Science 13
You read the following statement about two elements X and Y: One of the elements is a good conductor of electricity, and the other is a semiconductor. Experiments show that the first ionization energy of X is twice as great as that of Y. Which element has the greater metallic character?

Chapter: Problem: 7.57

Chemistry: The Central Science 13
Discussing this chapter, a classmate says, An element that commonly forms a cation is a metal. Do you agree or disagree? Explain your answer.

Chapter: Problem: 7.58

Chemistry: The Central Science 13
Discussing this chapter, a classmate says, Since elements that form cations are metals and elements that form anions are nonmetals, elements that do not form ions are metalloids. Do you agree or disagree? Explain your answer.

Chapter: Problem: 7.59

Chemistry: The Central Science 13
Predict whether each of the following oxides is ionic or molecular: SnO2, Al2O3, CO2, Li2O, Fe2O3, H2O.

Chapter: Problem: 7.60

Chemistry: The Central Science 13
Some metal oxides, such as Sc2O3, do not react with pure water, but they do react when the solution becomes either acidic or basic. Do you expect Sc2O3 to react when the solution becomes acidic or when it becomes basic? Write a balanced chemical equation to support your answer

Chapter: Problem: 7.61a

Chemistry: The Central Science 13
(a) What is meant by the terms acidic oxide and basic oxide?

Chapter: Problem: 7.61b

Chemistry: The Central Science 13
(b) How can we predict whether an oxide will be acidic or basic based on its composition?

Chapter: Problem: 7.62

Chemistry: The Central Science 13
Arrange the following oxides in order of increasing acidity: CO2, CaO, Al2O3, SO3, SiO2, P2O5

Chapter: Problem: 7.63

Chemistry: The Central Science 13
Chlorine reacts with oxygen to form Cl2O7. (a) What is the name of this product (see Table 2.6)? (b) Write a balanced equation for the formation of Cl2O71l2 from the elements. (c) Under usual conditions, Cl2O7 is a colorless liquid with a boiling point of 81 C. Is this boiling point expected or surpr

Chapter: Problem: 7.64

Chemistry: The Central Science 13
An element X reacts with oxygen to form XO2 and with chlorine to form XCl4. XO2 is a white solid that melts at high temperatures (above 1000 C). Under usual conditions, XCl4 is a colorless liquid with a boiling point of 58 C. (a) XCl4 reacts with water to form XO2 and another product. What is the lik

Chapter: Problem: 7.65

Chemistry: The Central Science 13
Write balanced equations for the following reactions: (a) barium oxide with water, (b) iron(II) oxide with perchloric acid, (c) sulfur trioxide with water, (d) carbon dioxide with aqueous sodium hydroxide.

Chapter: Problem: 7.66

Chemistry: The Central Science 13
Write balanced equations for the following reactions: (a) potassium oxide with water, (b) diphosphorus trioxide with water, (c) chromium(III) oxide with dilute hydrochloric acid, (d) selenium dioxide with aqueous potassium hydroxide.

Chapter: Problem: 7.67a

Chemistry: The Central Science 13
(a) Why is calcium generally more reactive than magnesium?

Chapter: Problem: 7.67b

Chemistry: The Central Science 13
(b) Why is calcium generally less reactive than potassium?

Chapter: Problem: 7.68

Chemistry: The Central Science 13
Silver and rubidium both form +1 ions, but silver is far less reactive. Suggest an explanation, taking into account the ground-state electron configurations of these elements and their atomic radii.

Chapter: Problem: 7.69

Chemistry: The Central Science 13
Write a balanced equation for the reaction that occurs in each of the following cases: (a) Potassium metal is exposed to an atmosphere of chlorine gas. (b) Strontium oxide is added to water. (c) A fresh surface of lithium metal is exposed to oxygen gas. (d) Sodium metal reacts with molten sulfur

Chapter: Problem: 7.70

Chemistry: The Central Science 13
Write a balanced equation for the reaction that occurs in each of the following cases: (a) Cesium is added to water. (b) Strontium is added to water. (c) Sodium reacts with oxygen. (d) Calcium reacts with iodine

Chapter: Problem: 7.71a

Chemistry: The Central Science 13
(a) As described in Section 7.7, the alkali metals react with hydrogen to form hydrides and react with halogens to form halides. Compare the roles of hydrogen and halogens in these reactions. How are the forms of hydrogen and halogens in the products alike?

Chapter: Problem: 7.71b

Chemistry: The Central Science 13
(b) Write balanced equations for the reaction of fluorine with calcium and for the reaction of hydrogen with calcium. What are the similarities among the products of these reactions?

Chapter: Problem: 7.72

Chemistry: The Central Science 13
Potassium and hydrogen react to form the ionic compound potassium hydride. (a) Write a balanced equation for this reaction. (b) Use data in Figures 7.10 and 7.12 to determine the energy change in kJ/mol for the following two reactions: K1g2 + H1g2 K+1g2 + H-1g2 K1g2 + H1g2 K-1g2 + H+1g2 (c) Based on

Chapter: Problem: 7.73

Chemistry: The Central Science 13
Compare the elements bromine and chlorine with respect to the following properties: (a) electron configuration, (b) most common ionic charge, (c) first ionization energy, (d) reactivity toward water, (e) electron affinity, (f) atomic radius. Account for the differences between the two elements.

Chapter: Problem: 7.74

Chemistry: The Central Science 13
Little is known about the properties of astatine, At, because of its rarity and high radioactivity. Nevertheless, it is possible for us to make many predictions about its properties. (a) Do you expect the element to be a gas, liquid, or solid at room temperature? Explain. (b) Would you expect At to b

Chapter: Problem: 7.75

Chemistry: The Central Science 13
Until the early 1960s the group 8A elements were called the inert gases. (a) Why was the term inert gases dropped? (b) What discovery triggered this change in name? (c) What name is applied to the group now?

Chapter: Problem: 7.76a

Chemistry: The Central Science 13
(a) Why does xenon react with fluorine, whereas neon does not?

Chapter: Problem: 7.76b

Chemistry: The Central Science 13
(b) Using appropriate reference sources, look up the bond lengths of XeF bonds in several molecules. How do these numbers compare to the bond lengths calculated from the atomic radii of the elements?

Chapter: Problem: 7.77

Chemistry: The Central Science 13
Write a balanced equation for the reaction that occurs in each of the following cases: (a) Ozone decomposes to dioxygen. (b) Xenon reacts with fluorine. (Write three different equations.) (c) Sulfur reacts with hydrogen gas. (d) Fluorine reacts with water.

Chapter: Problem: 7.78

Chemistry: The Central Science 13
Write a balanced equation for the reaction that occurs in each of the following cases: (a) Chlorine reacts with water. (b) Barium metal is heated in an atmosphere of hydrogen gas. (c) Lithium reacts with sulfur. (d) Fluorine reacts with magnesium metal.

Chapter: Problem: 7.79

Chemistry: The Central Science 13
Consider the stable elements through lead 1Z = 822. In how many instances are the atomic weights of the elements out of order relative to the atomic numbers of the elements?

Chapter: Problem: 7.80

Chemistry: The Central Science 13
Figure 7.4 shows the radial probability distribution functions for the 2s orbitals and 2p orbitals. (a) Which orbital, 2s or 2p, has more electron density close to the nucleus? (b) How would you modify Slaters rules to adjust for the difference in electronic penetration of the nucleus for the 2s and

Chapter: Problem: 7.81a

Chemistry: The Central Science 13
(a) If the core electrons were totally effective at screening the valence electrons and the valence electrons provided no screening for each other, what would be the effective nuclear charge acting on the 3s and 3p valence electrons in P?

Chapter: Problem: 7.81b

Chemistry: The Central Science 13
(b) Repeat these calculations using Slaters rules.

Chapter: Problem: 7.81c

Chemistry: The Central Science 13
(c) Detailed calculations indicate that the effective nuclear charge is 5.6+ for the 3s electrons and 4.9+ for the 3p electrons. Why are the values for the 3s and 3p electrons different?

Chapter: Problem: 7.81d

Chemistry: The Central Science 13
(d) If you remove a single electron from a P atom, which orbital will it come from?

Chapter: Problem: 7.82

Chemistry: The Central Science 13
As we move across a period of the periodic table, why do the sizes of the transition elements change more gradually than those of the representative elements?

Chapter: Problem: 7.83

Chemistry: The Central Science 13
In the series of group 5A hydrides, of general formula MH3, the measured bond distances are PH, 1.419 ; AsH, 1.519 ; SbH, 1.707 . (a) Compare these values with those estimated by use of the atomic radii in Figure 7.7. (b) Explain the steady increase in MH bond distance in this series in terms of the

Chapter: Problem: 7.84

Chemistry: The Central Science 13
In Table 7.8, the bonding atomic radius of neon is listed as 0.58 , whereas that for xenon is listed as 1.40 . A classmate of yours states that the value for Xe is more realistic than the one for Ne. Is she correct? If so, what is the basis for her statement?

Chapter: Problem: 7.85

Chemistry: The Central Science 13
The AsAs bond length in elemental arsenic is 2.48 . The ClCl bond length in Cl2 is 1.99 . (a) Based on these data, what is the predicted AsCl bond length in arsenic trichloride, AsCl3, in which each of the three Cl atoms is bonded to the As atom? (b) What bond length is predicted for AsCl3, using the

Chapter: Problem: 7.86

Chemistry: The Central Science 13
The following observations are made about two hypothetical elements A and B: The AA and BB bond lengths in elemental A and B are 2.36 and 1.94 , respectively. A and B react to form the binary compound AB2, which has a linear structure (that is B - A - B = 180). Based on these statements, predict the

Chapter: Problem: 7.87

Chemistry: The Central Science 13
Elements in group 7A in the periodic table are called the halogens; elements in group 6A are called the chalcogens. (a) What is the most common oxidation state of the chalcogens compared to the halogens? (b) For each of the following periodic properties, state whether the halogens or the chalcogens h

Chapter: Problem: 7.88

Chemistry: The Central Science 13
Note from the following table that there is a significant increase in atomic radius upon moving from Y to La whereas the radii of Zr to Hf are the same. Suggest an explanation for this effect. Atomic Radii () Sc 1.70 Ti 1.60 Y 1.90 Zr 1.75 La 2.07 Hf 1.75

Chapter: Problem: 7.89a

Chemistry: The Central Science 13
(a) Which ion is smaller, Co3+ or Co4+?

Chapter: Problem: 7.89b

Chemistry: The Central Science 13
(b) In a lithium-ion battery that is discharging to power a device, for every Li + that inserts into the lithium cobalt oxide electrode, a Co4+ ion must be reduced to a Co3+ ion to balance charge. Using the CRC Handbook of Chemistry and Physics or other standard reference, find the ionic radii of Li

Chapter: Problem: 7.89c

Chemistry: The Central Science 13
(c) Will the lithium cobalt electrode expand or contract as lithium ions are inserted?

Chapter: Problem: 7.89d

Chemistry: The Central Science 13
(d) Lithium is not nearly as abundant as sodium. If sodium ion batteries were developed that function as lithium ion ones, do you think sodium cobalt oxide would still work as the electrode material? Explain.

Chapter: Problem: 7.89e

Chemistry: The Central Science 13
e) If you dont think cobalt would work as the redox-active partner ion in the sodium version of the electrode, suggest an alternative metal ion and explain your reasoning.

Chapter: Problem: 7.90

Chemistry: The Central Science 13
The ionic substance strontium oxide, SrO, forms from the reaction of strontium metal with molecular oxygen. The arrangement of the ions in solid SrO is analogous to that in solid NaCl: (a) Write a balanced equation for the formation of SrO(s) from its elements. (b) Based on the ionic radii in Figure

Chapter: Problem: 7.91

Chemistry: The Central Science 13
Explain the variation in the ionization energies of carbon, as displayed in this graph: 1 2 3 4 5 6 10,000 20,000 30,000 40,000 50,000 Ionization number Ionization energies of carbon (kJ mol1 )

Chapter: Problem: 7.92

Chemistry: The Central Science 13
Group 4A elements have much more negative electron affinities than their neighbors in groups 3A and 5A (see Figure 7.12). Which of the following statements best explains this observation? (i) The group 4A elements have much higher first ionization energies than their neighbors in groups 3A and 5A. (i

Chapter: Problem: 7.93

Chemistry: The Central Science 13
In the chemical process called electron transfer, an electron is transferred from one atom or molecule to another. (We will talk about electron transfer extensively in Chapter 20.) A simple electron transfer reaction is A1g2 + A1g2 A+1g2 + A-1g2 In terms of the ionization energy and electron affinity

Chapter: Problem: 7.94a

Chemistry: The Central Science 13
(a) Use orbital diagrams to illustrate what happens when an oxygen atom gains two electrons.

Chapter: Problem: 7.94b

Chemistry: The Central Science 13
(b) Why does O3 - not exist?

Chapter: Problem: 7.95

Chemistry: The Central Science 13
Use electron configurations to explain the following observations: (a) The first ionization energy of phosphorus is greater than that of sulfur. (b) The electron affinity of nitrogen is lower (less negative) than those of both carbon and oxygen. (c) The second ionization energy of oxygen is greater t

Chapter: Problem: 7.96

Chemistry: The Central Science 13
Identify two ions that have the following ground-state electron configurations: (a) [Ar], (b) 3Ar43d5 , (c) 3Kr45s 2 4d10 .

Chapter: Problem: 7.97

Chemistry: The Central Science 13
Which of the following chemical equations is connected to the definitions of (a) the first ionization energy of oxygen, (b) the second ionization energy of oxygen, and (c) the electron affinity of oxygen? (i) O1g2 + e- O-1g2 (ii) O1g2 O+1g2 + e- (iii) O1g2 + 2e- O2-1g2 (iv) O1g2 O2+1g2 + 2e- (v) O+1g

Chapter: Problem: 7.98

Chemistry: The Central Science 13
The electron affinities, in kJ>mol, for the group 1B and group 2B metals are as follows: Hg > 0 Au 223 Cd > 0 Ag 126 Zn > 0 Cu 119 (a) Why are the electron affinities of the group 2B elements greater than zero? (b) Why do the electron affinities of the group 1B elements become more negative as we mov

Chapter: Problem: 7.99

Chemistry: The Central Science 13
Hydrogen is an unusual element because it behaves in some ways like the alkali metal elements and in other ways like nonmetals. Its properties can be explained in part by its electron configuration and by the values for its ionization energy and electron affinity. (a) Explain why the electron affinit

Chapter: Problem: 7.100

Chemistry: The Central Science 13
The first ionization energy of the oxygen molecule is the energy required for the following process: O21g2 O2 +1g2 + eThe energy needed for this process is 1175 kJ>mol, very similar to the first ionization energy of Xe. Would you expect O2 to react with F2? If so, suggest a product or products of thi

Chapter: Problem: 7.101

Chemistry: The Central Science 13
It is possible to define metallic character as we do in this book and base it on the reactivity of the element and the ease with which it loses electrons. Alternatively, one could measure how well electricity is conducted by each of the elements to determine how metallic the elements are. On the basi

Chapter: Problem: 7.102

Chemistry: The Central Science 13
Which of the following is the expected product of the reaction of K(s) and H21g2? (i) KH(s), (ii) K2H1s2, (iii) KH21s2, (iv) K2H21s2, or (v) K(s) and H21g2 will not react with one another.

Chapter: Problem: 7.103

Chemistry: The Central Science 13
Elemental cesium reacts more violently with water than does elemental sodium. Which of the following best explains this difference in reactivity? (i) Sodium has greater metallic character than does cesium. (ii) The first ionization energy of cesium is less than that of sodium. (iii) The electron affi

Chapter: Problem: 7.104a

Chemistry: The Central Science 13
(a) One of the alkali metals reacts with oxygen to form a solid white substance. When this substance is dissolved in water, the solution gives a positive test for hydrogen peroxide, H2O2. When the solution is tested in a burner flame, a lilac-purple flame is produced. What is the likely identity of t

Chapter: Problem: 7.104b

Chemistry: The Central Science 13
(b) Write a balanced chemical equation for the reaction of the white substance with water.

Chapter: Problem: 7.105

Chemistry: The Central Science 13
Zinc in its 2+ oxidation state is an essential metal ion for life. Zn2+ is found bound to many proteins that are involved in biological processes, but unfortunately Zn2+ is hard to detect by common chemical methods. Therefore, scientists who are interested in studying Zn2+-containing proteins frequen

Chapter: Problem: 7.106

Chemistry: The Central Science 13
A historian discovers a nineteenth-century notebook in which some observations, dated 1822, were recorded on a substance thought to be a new element. Here are some of the data recorded in the notebook: Ductile, silver-white, metallic looking. Softer than lead. Unaffected by water. Stable in air. Melt

Chapter: Problem: 7.107

Chemistry: The Central Science 13
In April 2010, a research team reported that it had made Element 117. This discovery was confirmed in 2012 by additional experiments. Write the ground-state electron configuration for Element 117 and estimate values for its first ionization energy, electron affinity, atomic size, and common oxidation

Chapter: Problem: 7.108

Chemistry: The Central Science 13
We will see in Chapter 12 that semiconductors are materials that conduct electricity better than nonmetals but not as well as metals. The only two elements in the periodic table that are technologically useful semiconductors are silicon and germanium. Integrated circuits in computer chips today are b

Chapter: Problem: 7.109

Chemistry: The Central Science 13
Moseley established the concept of atomic number by studying X rays emitted by the elements. The X rays emitted by some of the elements have the following wavelengths: Element Wavelength () Ne 14.610 Ca 3.358 Zn 1.435 Zr 0.786 Sn 0.491 (a) Calculate the frequency, n, of the X rays emitted by each of

Chapter: Problem: 7.110a

Chemistry: The Central Science 13
(a) Write the electron configuration for Li and estimate the effective nuclear charge experienced by the valence electron.

Chapter: Problem: 7.110b

Chemistry: The Central Science 13
(b) The energy of an electron in a one-electron atom or ion equals 1-2.18 * 10-18 J2 a Z2 n2 b, where Z is the nuclear charge and n is the principal quantum number of the electron. Estimate the first ionization energy of Li

Chapter: Problem: 7.110c

Chemistry: The Central Science 13
(c) Compare the result of your calculation with the value reported in Table 7.4 and explain the difference

Chapter: Problem: 7.110d

Chemistry: The Central Science 13
(d) What value of the effective nuclear charge gives the proper value for the ionization energy? Does this agree with your explanation in part (c)?

Chapter: Problem: 7.111

Chemistry: The Central Science 13
One way to measure ionization energies is ultraviolet photoelectron spectroscopy (PES), a technique based on the photoelectric effect. (Section 6.2) In PES, monochromatic light is directed onto a sample, causing electrons to be emitted. The kinetic energy of the emitted electrons is measured. The dif

Chapter: Problem: 7.112

Chemistry: The Central Science 13
Mercury in the environment can exist in oxidation states 0, +1, and +2. One major question in environmental chemistry research is how to best measure the oxidation state of mercury in natural systems; this is made more complicated by the fact that mercury can be reduced or oxidized on surfaces differ

Chapter: Problem: 7.113

Chemistry: The Central Science 13
When magnesium metal is burned in air (Figure 3.6), two products are produced. One is magnesium oxide, MgO. The other is the product of the reaction of Mg with molecular nitrogen, magnesium nitride. When water is added to magnesium nitride, it reacts to form magnesium oxide and ammonia gas. (a) Based

Chapter: Problem: 7.114a

Chemistry: The Central Science 13
(a) The measured BiBr bond length in bismuth tribromide, BiBr3, is 2.63 . Based on this value and the data in Figure 7.8, predict the atomic radius of Bi.

Chapter: Problem: 7.114b

Chemistry: The Central Science 13
(b) Bismuth tribromide is soluble in acidic solution. It is formed by treating solid bismuth(III) oxide with aqueous hydrobromic acid. Write a balanced chemical equation for this reaction.

Chapter: Problem: 7.114c

Chemistry: The Central Science 13
(c) While bismuth(III) oxide is soluble in acidic solutions, it is insoluble in basic solutions such as NaOH(aq). Based on these properties, is bismuth characterized as a metallic, metalloid, or nonmetallic element?

Chapter: Problem: 7.114d

Chemistry: The Central Science 13
(d) Treating bismuth with fluorine gas forms BiF5. Use the electron configuration of Bi to explain the formation of a compound with this formulation.

Chapter: Problem: 7.114e

Chemistry: The Central Science 13
(e) While it is possible to form BiF5 in the manner just described, pentahalides of bismuth are not known for the other halogens. Explain why the pentahalide might form with fluorine but not with the other halogens. How does the behavior of bismuth relate to the fact that xenon reacts with fluorine t

Chapter: Problem: 7.115

Chemistry: The Central Science 13
Potassium superoxide, KO2, is often used in oxygen masks (such as those used by firefighters) because KO2 reacts with CO2 to release molecular oxygen. Experiments indicate that 2 mol of KO21s2 react with each mole of CO21g2. (a) The products of the reaction are K2CO31s2 and O21g2. Write a balanced eq

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