?Classify each element as a metal, nonmetal, or metalloid.(a) Sr(b) Mg(c) F(d) N(e) As

What did Democritus contribute to our modern understanding of matter?

What are three main ideas in Dalton’s atomic theory?

Describe Rutherford’s gold foil experiment and the results of that experiment. How did these results refute the plum pudding model of the atom?

What are the main ideas in the nuclear theory of the atom?

List the three subatomic particles and their properties.

What is electrical charge?

Is matter usually charge-neutral? How would matter be different if it were not charge-neutral?

What does the atomic number of an element specify?

What is a chemical symbol?

List some examples of how elements were named.

What was Dmitri Mendeleev’s main contribution to our modern understanding of chemistry?

What is the main idea in the periodic law?

How is the periodic table organized?

What are the properties of metals? Where are metals found on the periodic table?

What are the properties of nonmetals? Where are nonmetals found on the periodic table?

Where on the periodic table are metalloids found?

What is a family or group of elements?

Locate each group of elements on the periodic table and list its group number. (a) alkali metals (b) alkaline earth metals (c) halogens (d) noble gases

What is an ion?

What is an anion? What is a cation?

Locate each group on the periodic table and list the charge of the ions it tends to form. (a) Group 1A (b) Group 2A (c) Group 3A (d) Group 6A (e) Group 7A

What are isotopes?

What is the percent natural abundance of isotopes?

What is the mass number of an isotope?

What notations are commonly used to specify isotopes? What do each of the numbers in these symbols mean?

What is the atomic mass of an element?

Which statements are inconsistent with Dalton’s atomic theory as it was originally stated? Explain your answers. (a) All carbon atoms are identical. (b) Helium atoms can be split into two hydrogen atoms. (c) An oxygen atom combines with 1.5 hydrogen atoms to form water molecules. (d) Two oxygen atoms combine with a carbon atom to form carbon dioxide molecules.

Which statements are consistent with Dalton’s atomic theory as it was originally stated? Explain your answers. (a) Calcium and titanium atoms have the same mass. (b) Neon and argon atoms are the same. (c) All cobalt atoms are identical. (d) Sodium and chlorine atoms combine in a 1:1 ratio to form sodium chloride.

Which statements are inconsistent with Rutherford’s nuclear theory as it was originally stated? Explain your answers. (a) Helium atoms have two protons in the nucleus and two electrons outside the nucleus. (b) Most of the volume of hydrogen atoms is due to the nucleus. (c) Aluminum atoms have 13 protons in the nucleus and 22 electrons outside the nucleus. (d) The majority of the mass of nitrogen atoms is due to their 7 electrons.

Which statements are consistent with Rutherford’s nuclear theory as it was originally stated? Explain your answers. (a) Atomic nuclei are small compared to the size of atoms. (b) The volume of an atom is mostly empty space. (c) Neutral potassium atoms contain more protons than electrons. (d) Neutral potassium atoms contain more neutrons than protons.

If atoms are mostly empty space and atoms compose all ordinary matter, why does solid matter seem to have no space within it?

Rutherford’s experiment indicated that matter was not as uniform as it appears. What part of his experimental results implied this idea? Explain.

Which statement about electrons is true? (a) Electrons attract one another. (b) Electrons are repelled by protons. (c) Some electrons have a charge of 1- and some have no charge. (d) Electrons are much lighter than neutrons.

Which statement about electrons is false? (a) Most atoms have more electrons than protons. (b) Electrons have a charge of 1-. (c) If an atom has an equal number of protons and electrons, it will be charge-neutral. (d) Electrons experience an attraction to protons.

Which statement about protons is true? (a) Protons have twice the mass of neutrons. (b) Protons have the same magnitude of charge as electrons but are opposite in sign. (c) Most atoms have more protons than electrons. (d) Protons have a charge of 1-.

Which statement about protons is false? (a) Protons have about the same mass as neutrons. (b) Protons have about the same mass as electrons. (c) All atoms have protons. (d) Protons have the same magnitude of charge as neutrons but are opposite in sign.

How many electrons would it take to equal the mass of a proton?

A helium nucleus has two protons and two neutrons. How many electrons would it take to equal the mass of a helium nucleus?

What mass of electrons is required to neutralize the charge of 1.0 g of protons?

What mass of protons is required to neutralize the charge of 1.0 g of electrons?

Find the atomic number (Z) for each element. (a) Fr (b) Kr (c) Pa (d) Ge (e) Al

Find the atomic number (Z) for each element. (a) Si (b) W (c) Ni (d) Rn (e) Sr

How many protons are in the nucleus of an atom of each element? (a) Ar (b) Sn (c) Xe (d) O (e) Tl

How many protons are in the nucleus of an atom of each element? (a) Ti (b) Li (c) U (d) Br (e) F

List the symbol and atomic number of each element. (a) carbon (b) nitrogen (c) sodium (d) potassium (e) copper

List the symbol and atomic number of each element. (a) boron (b) neon (c) silver (d) mercury (e) curium

List the name and the atomic number of each element. (a) Mn (b) Ag (c) Au (d) Pb (e) S

List the name and the atomic number of each element. (a) Y (b) N (c) Ne (d) K (e) Mo

Fill in the blanks to complete the table.

Fill in the blanks to complete the table.

Classify each element as a metal, nonmetal, or metalloid. (a) Sr (b) Mg (c) F (d) N (e) As

Classify each element as a metal, nonmetal, or metalloid. (a) Na (b) Ge (c) Si (d) Br (e) Ag

Which elements would you expect to lose electrons in chemical changes? (a) potassium (b) sulfur (c) fluorine (d) barium (e) copper

Which elements would you expect to gain electrons in chemical changes? (a) nitrogen (b) iodine (c) tungsten (d) strontium (e) gold

Which elements are main-group elements? (a) Te (b) K (c) V (d) Re (e) Ag

Which elements are not main-group elements? (a) Al (b) Br (c) Mo (d) Cs (e) Pb

Which elements are alkaline earth metals? (a) sodium (b) aluminum (c) calcium (d) barium (e) lithium

Which elements are alkaline earth metals? (a) rubidium (b) tungsten (c) magnesium (d) cesium (e) beryllium

Which elements are alkali metals? (a) barium (b) sodium (c) gold (d) tin (e) rubidium

Which elements are alkali metals? (a) scandium (b) iron (c) potassium (d) lithium (e) cobalt

Classify each element as a halogen, a noble gas, or neither. (a) Cl (b) Kr (c) F (d) Ga (e) He

Classify each element as a halogen, a noble gas, or neither. (a) Ne (b) Br (c) S (d) Xe (e) I

To what group number does each element belong? (a) oxygen (b) aluminum (c) silicon (d) tin (e) phosphorus

To what group number does each element belong? (a) germanium (b) nitrogen (c) sulfur (d) carbon (e) boron

Which element do you expect to be most like sulfur? Why? (a) nitrogen (b) oxygen (c) fluorine (d) lithium (e) potassium

Which element do you expect to be most like magnesium? Why? (a) potassium (b) silver (c) bromine (d) calcium (e) lead

Which pair of elements do you expect to be most similar? Why? (a) Si and P (b) Cl and F (c) Na and Mg (d) Mo and Sn (e) N and Ni

Which pair of elements do you expect to be most similar? Why? (a) Ti and Ga (b) N and O (c) Li and Na (d) Ar and Br (e) Ge and Ga

Which element is a main-group nonmetal? (a) K (b) Fe (c) Sn (d) S

Which element is a row 5 transition element? (a) Sr (b) Pd (c) P (d) V

Fill in the blanks to complete the table.

The coldest temperature ever recorded in Iowa was -47 °F on February 3, 1998. Convert this temperature to kelvins and degrees Celsius.

Determine the charge of each ion. (a) oxygen ion with 10 electrons (b) aluminum ion with 10 electrons (c) titanium ion with 18 electrons (d) iodine ion with 54 electrons

Determine the charge of each ion. (a) tungsten ion with 68 electrons (b) tellurium ion with 54 electrons (c) nitrogen ion with 10 electrons (d) barium ion with 54 electrons

Determine the number of protons and electrons in each ion. (a) \(\mathrm{Na}^{+}\) (b) \(\mathrm{Ba}^{2+}\) (c) \(\mathrm{O}^{2-}\) (d) \(\mathrm{Co}^{3+}\) Text Transcription: Na^+ Ba^2+ O^2- Co^3+

Determine the number of protons and electrons in each ion. (a) \(\mathrm{Al}^{3+}\) (b) \(\mathrm{S}^{2-}\) (c) \(\mathbf{I}^{-}\) (d) \(\mathrm{Ag}^{+}\) Text Transcription: Al^3+ S^2- I^- Ag^+

Determine whether each statement is true or false. If false, correct it. (a) The \(\mathrm{Ti}^{2+}\) ion contains 22 protons and 24 electrons. (b) The \(\mathbf{I}^{-}\) ion contains 53 protons and 54 electrons. (c) The \(\mathrm{Mg}^{2+}\) ion contains 14 protons and 12 electrons. (d) The \(\mathrm{O}^{2-}\) ion contains 8 protons and 10 electrons. Text Transcription: Ti^2+ I^- Mg^2+ O^2-

Determine whether each statement is true or false. If false, correct it. (a) The \(\mathrm{Fe}^{2+}\) ion contains 29 protons and 26 electrons. (b) The \(\mathrm{Cs}^{+}\) ion contains 55 protons and 56 electrons. (c) The \(\mathrm{Se}^{2-}\) ion contains 32 protons and 34 electrons. (d) The \(\mathrm{Li}^{+}\) ion contains 3 protons and 2 electrons. Text Transcription: Fe^2+ Cs^+ Se^2- Li^+

Predict the ion formed by each element. (a) Rb (b) K (c) Al (d) O

Predict the ion formed by each element. (a) F (b) N (c) Mg (d) Na

Predict how many electrons each element will most likely gain or lose. (a) Ga (b) Li (c) Br (d) S

Predict how many electrons each element will most likely gain or lose. (a) I (b) Ba (c) Cs (d) Se

Fill in the blanks to complete the table.

Fill in the blanks to complete the table.

Determine the atomic number and mass number for each isotope. (a) the hydrogen isotope with 2 neutrons (b) the chromium isotope with 28 neutrons (c) the calcium isotope with 22 neutrons (d) the tantalum isotope with 109 neutrons

How many neutrons are in an atom with each atomic number and mass number? (a) Z = 28, A = 59 (b) Z = 92, A = 235 (c) Z = 21, A = 46 (d) Z = 18, A = 42

Write isotopic symbols in the form \({ }_{Z}^{A} X\) for each isotope. (a) the oxygen isotope with 8 neutrons (b) the fluorine isotope with 10 neutrons (c) the sodium isotope with 12 neutrons (d) the aluminum isotope with 14 neutrons Text Transcription: Z^A X

Write isotopic symbols in the form X-A (for example, C-13) for each isotope. (a) the iodine isotope with 74 neutrons (b) the phosphorus isotope with 16 neutrons (c) the uranium isotope with 234 neutrons (d) the argon isotope with 22 neutrons

Write the symbol for each isotope in the form \({ }_{Z}^{A} X\). (a) cobalt-60 (b) neon-22 (c) iodine-131 (d) plutonium-244 Text Transcription: Z^A X

Write the symbol for each isotope in the form \({ }_{Z}^{A} X\). (a) U-235 (b) V-52 (c) P-32 (d) Xe-144 Text Transcription: Z^A X

Determine the number of protons and neutrons in each isotope. (a) \({ }_{11}^{23} \mathrm{Na}\) (b) \({ }_{88}^{266} \mathrm{Ra}\) (c) \({ }_{32}^{208} \mathrm{~Pb}\) (d) \({ }_{7}^{14} \mathrm{~N}\) Text Transcription: _11^23 Na _88^266 Ra _32^208 Pb _7^14 N

Determine the number of protons and neutrons in each isotope. (a) \({ }_{15}^{33} \mathrm{P}\) (b) \({ }_{19}^{40} \mathrm{~K}\) (c) \({ }_{86}^{222} \mathrm{Rn}\) (d) \({ }_{43}^{99} \mathrm{Tc}\) Text Transcription: _15^33 P _19^40 K _86^222 Rn _43^99Tc

Carbon-14, present within living organisms and substances derived from living organisms, is often used to establish the age of fossils and artifacts. Determine the number of protons and neutrons in a carbon-14 isotope and write its symbol in the form \({ }_{Z}^{A} X\). Text Transcription: Z^A X

Plutonium-239 is used in nuclear bombs. Determine the number of protons and neutrons in plutonium-239 and write its symbol in the form \({ }_{Z}^{A} X\). Text Transcription: Z^A X

Rubidium has two naturally occurring isotopes: Rb-85 with mass 84.9118 amu and a natural abundance of 72.17%, and Rb-87 with mass 86.9092 amu and a natural abundance of 27.83%. Calculate the atomic mass of rubidium.

Silicon has three naturally occurring isotopes: Si-28 with mass 27.9769 amu and a natural abundance of 92.21%, Si-29 with mass 28.9765 amu and a natural abundance of 4.69%, and Si-30 with mass 29.9737 amu and a natural abundance of 3.10%. Calculate the atomic mass of silicon.

Bromine has two naturally occurring isotopes (Br-79 and Br-81) and an atomic mass of 79.904 amu. (a) If the natural abundance of Br-79 is 50.69%, what is the natural abundance of Br-81? (b) If the mass of Br-81 is 80.9163 amu, what is the mass of Br-79?

Silver has two naturally occurring isotopes (Ag-107 and Ag-109). (a) Use the periodic table to find the atomic mass of silver. (b) If the natural abundance of Ag-107 is 51.84%, what is the natural abundance of Ag-109? (c) If the mass of Ag-107 is 106.905 amu, what is the mass of Ag-109?

An element has two naturally occurring isotopes. Isotope 1 has a mass of 120.9038 amu and a relative abundance of 57.4%, and isotope 2 has a mass of 122.9042 amu and a relative abundance of 42.6%. Find the atomic mass of this element and, referring to the periodic table, identify it.

Copper has two naturally occurring isotopes. Cu-63 has a mass of 62.939 amu and relative abundance of 69.17%. Use the atomic weight of copper to determine the mass of the other copper isotope.

Electrical charge is sometimes reported in coulombs (C). On this scale, 1 electron has a charge of \(-1.6 \times 10^{-19}\) C. Suppose your body acquires -125 mC (millicoulombs) of charge on a dry day. How many excess electrons has it acquired? (Hint: Use the charge of an electron in coulombs as a conversion factor between charge and number of electrons.) Text Transcription: -1.6 times 10^-19

How many excess protons are in a positively charged object with a charge of +398 mC (millicoulombs)? The charge of 1 proton is \(+1.6 \times 10^{-19}\) C. (Hint: Use the charge of the proton in coulombs as a conversion factor between charge and number of protons.) Text Transcription: +1.6 times 10^-19

The hydrogen atom contains 1 proton and 1 electron. The radius of the proton is approximately 1.0 fm (femtometer), and the radius of the hydrogen atom is approximately 53 pm (picometers). Calculate the volume of the nucleus and the volume of the atom for hydrogen. What percentage of the hydrogen atom’s volume does the nucleus occupy? (Hint: Convert both given radii to m, and then calculate their volumes using the formula for the volume of a sphere, which is \(V=\frac{4}{3} \pi r^{3}\).) Text Transcription: V=43 \pi r^3

Carbon-12 contains 6 protons and 6 neutrons. The radius of the nucleus is approximately 2.7 fm, and the radius of the atom is approximately 70 pm. Calculate the volume of the nucleus and the volume of the atom. What percentage of the carbon atom’s volume does the nucleus occupy? (Hint: Convert both given radii to m, and then calculate their volumes using the formula for the volume of a sphere, which is \(V=\frac{4}{3} \pi r^{3}\).) Text Transcription: V=43 \pi r^3

Prepare a table like Table 4.2 for the four different isotopes of Sr that have the natural abundances and masses listed here. Sr-84 0.56% 83.9134 amu Sr-86 9.86% 85.9093 amu Sr-87 7.00% 86.9089 amu Sr-88 82.58% 87.9056 amu Use your table and the listed atomic masses to calculate the atomic mass of strontium.

Determine the number of protons and neutrons in each isotope of chromium and use the listed natural abundances and masses to calculate its atomic mass. Cr-50 4.345% 49.9460 amu Cr-52 83.79% 51.9405 amu Cr-53 9.50% 52.9407 amu Cr-54 2.365% 53.9389 amu

Fill in the blanks to complete the table.

Fill in the blanks to complete the table.

Europium has two naturally occurring isotopes: Eu-151 with a mass of 150.9198 amu and a natural abundance of 47.8%, and Eu-153. Use the atomic mass of europium to find the mass and natural abundance of Eu-153.

Rhenium has two naturally occurring isotopes: Re-185 with a natural abundance of 37.40% and Re-187 with a natural abundance of 62.60%. The sum of the masses of the two isotopes is 371.9087 amu. Find the masses of the individual isotopes.

Chapter 1 describes the difference between observations, laws, and theories. Cite two examples of theories from Chapter 4 and explain why they are theories.

Chapter 1 describes the difference between observations, laws, and theories. Cite one example of a law from Chapter 4 and explain why it is a law.

The atomic mass of fluorine is 19.00 amu, and all fluorine atoms in a naturally occurring sample of fluorine have this mass. The atomic mass of chlorine is 35.45 amu, but no chlorine atoms in a naturally occurring sample of chlorine have this mass. Provide an explanation for the difference.

The atomic mass of germanium is 72.61 amu. Is it likely that any individual germanium atoms have a mass of 72.61 amu?

Copper has only two naturally occurring isotopes, Cu-63 and Cu-65. The mass of Cu-63 is 62.9396 amu, and the mass of Cu-65 is 64.9278 amu. Use the atomic mass of copper to determine the relative abundance of each isotope in a naturally occurring sample. (Hint: The relative abundances of the two isotopes sum to 100%.)

Complete each ionization equation. (a) \(\mathrm{Mg} \longrightarrow\) ____ + \(2 \mathrm{e}^{-}\) (b) \(\mathrm{Ba} \longrightarrow \mathrm{Ba}^{2+}\) + ____ (c) \(\mathrm{I}+\mathrm{e}^{-} \longrightarrow\) ____ (d) \(\mathrm{Al} \longrightarrow\) ____ + \(3 \mathrm{e}^{-}\) Text Transcription: Mg longrightarrow___+2 e^- Ba longrightarrow Ba^2+____ I+\e^- longrightarrow _____ Al longrightarrow _____+ 3 e^-

Gallium has only two naturally occurring isotopes, Ga-69 and Ga-71. The mass of Ga-69 is 68.9256 amu, and the mass of Ga-71 is 70.9247 amu. Use the atomic mass of gallium to determine the relative abundance of each isotope in a naturally occurring sample.

The figure shown here is a representation of 50 atoms of a fictitious element with the symbol Nt and atomic number 120. Nt has three isotopes represented by the following colors: Nt-304 (red), Nt-305 (blue), and Nt-306 (green). (a) Assuming that the figure is statistically representative of naturally occurring Nt, what is the percent natural abundance of each Nt isotope? (b) Use the listed masses of each isotope to calculate the atomic mass of Nt. Then draw a box for the element similar to the boxes for each element shown in the periodic table in the inside front cover of this book. Make sure your box includes the atomic number, symbol, and atomic mass. (Assume that the percentages from part a are correct to four significant figures.) Nt-304 303.956 amu Nt-305 304.962 amu Nt-306 305.978 amu

Neutron stars are believed to be composed of solid nuclear matter, primarily neutrons. (a) If the radius of a neutron is \(1.0 \times 10^{-13}\) cm, calculate its density in \(\mathrm{g} / \mathrm{cm}^{3}\). (volume of a sphere = \(=\frac{4}{3} \pi r^{3}\)) (b) Assuming that a neutron star has the same density as a neutron, calculate the mass in kilograms of a small piece of a neutron star the size of a spherical pebble with a radius of 0.10 mm. Text Transcription: 1.0times10^-13 g\cm^3 =\43\pir^3

Complete the following table.

Make a sketch of an oxygen atom. Include the correct number of protons, electrons, and neutrons for the most abundant isotope. Use the following symbols: proton = •, neutron = o, electron = •.

The table at right includes data similar to that used by Mendeleev when he made the periodic table. Write on a small card the symbol, atomic mass, and a stable compound formed by each element. Arrange your cards in order of increasing atomic mass. Do you observe any repeating patterns? Describe any patterns you observe. (Hint: There is one missing element somewhere in the pattern.)

Arrange the cards from Question 123 so that mass increases from left to right and elements with similar properties are above and below each other. Copy the periodic table you have invented onto a piece of paper. There is one element missing. Predict its mass and a stable compound it might form.

The graph at the right shows the atomic radius for the 19 elements in the periodic table. (a) Describe the trend in atomic radius in going from H (atomic number 1) to K (atomic number 19). (b) Find the three elements represented with blue dots on a periodic table. What do their placements in the table have in common? (c) Find the three elements represented with red dots on a periodic table. What do their placements in the table have in common? (d) Based on the graph, what is the radius of C?

Complete each ionization equation. (a) \(\mathrm{Na} \longrightarrow \mathrm{Na}^{+}\) + ___ (b) \(\mathrm{O}+2 \mathrm{e}^{-}\) ____ (c) \(\mathrm{Ca} \longrightarrow \mathrm{Ca}^{2+}\) + ____ (d) \(\mathrm{Cl}+\mathrm{e}^{-}\) ____ Text Transcription: Na longrightarrow Na^+ O+2 e^- Ca longrightarrow Ca^2+ Cl+e^-