Aldrin, a chlorinated insecticide now banned from use in

Give the structures of the likely products from reaction of 1 equivalent of HCl with 2-methyl-1,3-cyclohexadiene. Show both 1,2 and 1,4 adducts.

Give the structures of both 1,2 and 1,4 adducts resulting from reaction of 1 equivalent of HCl with 1,3-pentadiene.

Look at the possible carbocation intermediates produced during addition of HCl to 1,3-pentadiene (Problem 14-2), and predict which 1,2 adduct predominates. Which 1,4 adduct predominates?

Give the structures of both 1,2 and 1,4 adducts resulting from reaction of 1 equivalent of HBr with the following compound:

The 1,2 adduct and the 1,4 adduct formed by reaction of HBr with 1,3-butadiene are in equilibrium at \(\mathrm{40~^\circ C}\). Propose a mechanism by which the interconversion of products takes place. Equation Transcription: Text Transcription: 40^oC

Why do you suppose 1,4 adducts of 1,3-butadiene are generally more stable than 1,2 adducts?

Predict the product of the following Diels–Alder reaction:

Predict the product of the following Diels–Alder reaction: Equation Transcription: Text Transcription: C=C H_3C C-OCH_3

Which of the following alkenes would you expect to be good Diels–Alder dienophiles? ________________ Equation Transcription: Text Transcription: H_2C=CHCCl H_2C=CHCH_2CH_2COCH_3

Which of the following dienes have an s-cis conformation, and which have an s-trans conformation? Of the s-trans dienes, which can readily rotate to s-cis?

Predict the product of the following Diels–Alder reaction:

Draw a segment of the polymer that might be prepared from 2-phenyl-1,3- butadiene.

Show the mechanism of the acid-catalyzed polymerization of 1,3-butadiene.

Calculate the energy range of electromagnetic radiation in the UV region of the spectrum from 200 to 400 nm (see Section 12-5). How does this value compare with the values calculated previously for IR and NMR spectroscopy?

If pure vitamin A has \(\lambda_\mathrm{max}=325(\varepsilon=50,100)\), what is the vitamin A concentration in a sample whose absorbance at 325 nm is \(A=0.735\) in a cell with a pathlength of 1.00 cm? Equation Transcription: Text Transcription: lambda_max=325(epsilon=50,100) A=0.735

Which of the following compounds would you expect to show ultraviolet absorptions in the 200 to 400 nm range? Equation Transcription: Text Transcription: CH_3

Show the structures of all possible adducts of the following diene with 1 equivalent of HCl:

Show the product of the Diels–Alder reaction of the following diene with 3-buten-2-one, \(\mathrm{H_2C=CHCOCH_3}\). Make sure you show the full stereochemistry of the reaction product. ________________ Equation Transcription: Text Transcription: H_2C=CHCOCH_3

The following diene does not undergo Diels–Alder reactions. Explain.

The following model is that of an allylic carbocation intermediate formed by protonation of a conjugated diene with HBr. Show the structure of the diene and the structures of the inal reaction products.

Predict the major product(s) from the addition of 1 equivalent of HX and show the mechanism for each reaction below. ________________ Equation Transcription: Text Transcription: 40 ^oC CH_2 0 ^oC CH_2 CH_2

We’ve seen that the Diels–Alder cycloaddition reaction is a one-step, peri cyclic process that occurs through a cyclic transition state. Propose a mechanism for the following reaction: Equation Transcription: Text Transcription: H_2C=CH_2

In light of your answer to Problem 14-21 propose mechanisms for the reactions below. ________________ Equation Transcription: Text Transcription: CO_2CH_3 CO_2CH_3 CO_2CH_3 CO_2CH_3 CO_2 CH_3 CH_3 C{equiv}CH CH_3 CH_3 N_2

Luminol, which is used by forensic scientists to find blood, fluoresces as a result of Diels–Alder-like process. The dianion of luminol reacts with \(\mathrm{O_2}\) to form an unstable peroxide intermediate that then loses nitrogen to form a dicarboxylate and emit light. The process is similar to that in 14-21 and 14-22. Propose a mechanism for this process. ________________ Equation Transcription: Text Transcription: O_2 NH_2 O^- O^- NH_2 O^- O^- N_2

An extremely useful diene in the synthesis of many natural products is known as Danishefsky’s diene. This compound is useful because after the Diels–Alder reaction it can be converted into a product that could not be accessed by a typical Diels–Alder reaction. Show the Diels–Alder adduct and propose a mechanism that accounts for the final products. ________________ Equation Transcription: Text Transcription: OCH_3 (CH_3)_3SiO CH_2 CH_2 CH_3OH+(CH_3)_3SiCl

Give IUPAC names for the following compounds: ________________ Equation Transcription: Text Transcription: CH_3 CH_3CH=CCH=CHCH_3 H_2C=CHCH=CHCH=CHCH_3 CH_3CH=C=CHCH=CHCH_3 CH_2CH_2CH_3 CH_3CH=CCH=CH_2

Draw and name the six possible diene isomers of formula \(\mathrm{C_5H_8}\). Which of the six are conjugated dienes? Equation Transcription: Text Transcription: C_5H_8

What product(s) would you expect to obtain from reaction of 1,3-cyclohexadiene with each of the following? (a) 1 mol \(\mathrm{Br_2}\) in \(\mathrm{CH_2Cl_2}\) (b) \(\mathrm{O_3}\) followed by Zn (c) 1 mol HCl in ether (d) 1 mol DCl in ether (e) 3-Buten-2-one \(\mathrm{(H_2C=CHCOCH_3)}\) (f) Excess \(\mathrm{OsO_4}\), followed by \(\mathrm{NaHSO_3}\) ________________ Equation Transcription: Text Transcription: Br_2 CH_2Cl_2 O_3 (H_2C=CHCOCH_3) OsO_4 NaHSO_3

Electrophilic addition of \(\mathrm{Br_2}\) to isoprene (2-methyl-1,3-butadiene) yields the following product mixture: Of the 1,2-addition products, explain why 3,4-dibromo-3-methyl-1- butene (21%) predominates over 3,4-dibromo-2-methyl-1-butene (3%). Equation Transcription: Text Transcription: Br_2 Br_2 CH_3

Propose a structure for a conjugated diene that gives the same product from both 1,2 and 1,4-addition of HBr.

Draw the possible products resulting from addition of 1 equivalent of HCl to 1-phenyl-1,3-butadiene. Which would you expect to predominate, and why?

Predict the products of the following Diels–Alder reactions:

2,3-Di-tert-butyl-1,3-butadiene does not undergo Diels–Alder reactions. Explain.

Show the structure, including stereochemistry, of the product from the following Diels–Alder reaction: Equation Transcription: Text Transcription: CH_3OC COCH_3

How can you account for the fact that cis-1,3-pentadiene is much less reactive than trans-1,3-pentadiene in the Diels–Alder reaction?

Would you expect a conjugated diyne such as 1,3-butadiyne to undergo Diels–Alder reaction with a dienophile? Explain.

Reaction of isoprene (2-methyl-1,3-butadiene) with ethyl propenoate gives a mixture of two Diels–Alder adducts. Show the structure of each, and explain why a mixture is formed. Equation Transcription: Text Transcription: CO_2CH_2CH_3

Rank the following dienophiles in order of their expected reactivity in the Diels–Alder reaction. Equation Transcription: Text Transcription: CH_3 C=C C=C C=C H_3C H_3C CH_3 CH_3

1,3-Cyclopentadiene is very reactive in Diels–Alder cycloaddition reactions, but 1,3-cyclohexadiene is less reactive and 1,3-cycloheptadiene is nearly inert. Explain. (Molecular models are helpful.)

1,3-Pentadiene is much more reactive in Diels–Alder reactions than 2,4-pentadienal. Why might this be? Equation Transcription: Text Transcription: CH_3

How could you use Diels–Alder reactions to prepare the following products? Show the starting diene and dienophile in each case. ________________ Equation Transcription: Text Transcription: CO_2CH_3

Although the Diels–Alder reaction generally occurs between an electron rich diene and an electron-deficient dienophile, it is also possible to have inverse-demand Diels–Alder reactions between suitable electrondeicient conjugated double bonds and electron-rich alkenes. These reactions are particularly useful because they allow for the incorporation of heteroatoms into the new six-membered ring. Predict the products of each inverse-demand Diels–Alder reaction below. Be sure your products reflect the correct stereochemistry. If more than one regioisomer is possible, draw both. Equation Transcription: Text Transcription: CH_2 H_2C H_2C CO_2CH_3 H_2C OCH_3

Diene polymers contain occasional vinyl branches along the chain. How do you think these branches might arise?

Tires whose sidewalls are made of natural rubber tend to crack and weather rapidly in areas around cities where high levels of ozone and other industrial pollutants are found. Explain.

1,3-Cyclopentadiene polymerizes slowly at room temperature to yield a polymer that has no double bonds except on the ends. On heating, the polymer breaks down to regenerate 1,3-cyclopentadiene. Propose a structure for the product.

Arrange the molecules according to where you would expect to find their wavelength of maximum absorption in UV spectroscopy, from shortest to longest wavelength. (b) (a) (c) CH2 CH2 CH3 CH3 CH2 CH3 CH2 CH2

Which of the following compounds would you expect to have a p n p* UV absorption in the 200 to 400 nm range? CH2 (a) (b) (c) (CH3)2C C O Pyridine A ketene

Would you expect allene, H2CPCPCH2, to show a UV absorption in the 200 to 400 nm range? Explain.

The following ultraviolet absorption maxima have been measured: 1,3-Butadiene 217 nm 2-Methyl-1,3-butadiene 220 nm 1,3-Pentadiene 223 nm 2,3-Dimethyl-1,3-butadiene 226 nm 2,4-Hexadiene 227 nm 2,4-Dimethyl-1,3-pentadiene 232 nm 2,5-Dimethyl-2,4-hexadiene 240 nm What conclusion can you draw about the effect of alkyl substitution on UV absorption maxima? Approximately what effect does each added alkyl group have?

1,3,5-Hexatriene has lmax 5 258 nm. In light of your answer to Problem 14-48, approximately where would you expect 2,3-dimethyl-1,3,5- hexatriene to absorb?

b-Ocimene is a pleasant-smelling hydrocarbon found in the leaves of certain herbs. It has the molecular formula C10H16 and a UV absorption maximum at 232 nm. On hydrogenation with a palladium catalyst, 2,6-dimethyloctane is obtained. Ozonolysis of b-ocimene, followed by treatment with zinc and acetic acid, produces the following four fragments: Acetone CH3C O O CH3CCH3 CH O Malonaldehyde O O HCCH2CH Formaldehyde Pyruvaldehyde O HCH (a) How many double bonds does b-ocimene have? (b) Is b-ocimene conjugated or nonconjugated? (c) Propose a structure for b-ocimene. (d) Write the reactions, showing starting material and products

Draw the resonance forms that result when the dienes below are protonated. If the resonance forms differ in energy, identify the most stable one. (b) (a) (c)

Answer the questions below for 1,3,5-cycloheptatriene. (a) How many p atomic orbitals are in the conjugated system? (b) How many molecular orbitals describe the conjugated system? (c) How many molecular orbitals are bonding molecular orbitals? (d) How many molecular orbitals are anti-bonding molecular orbitals? (e) Which molecular orbitals are filled with electrons? (f) If this molecule were to absorb a photon of UV light an electron would move between which two molecular orbitals (be specif

Treatment of 3,4-dibromohexane with strong base leads to loss of 2 equivalents of HBr and formation of a product with formula C6H10. Three products are possible. Name each of the three, and tell how you would use 1H and 13C NMR spectroscopy to help identify them. How would you use UV spectroscopy?

Addition of HCl to 1-methoxycyclohexene yields 1-chloro-1-methoxycyclohexane as a sole product. Use resonance structures to explain why none of the other regioisomer is formed. OCH3 OCH3 C

Aldrin, a chlorinated insecticide now banned from use in the United States, can be made by DielsAlder reaction of hexachloro-1,3-cyclopentadiene with norbornadiene. What is the structure of aldrin? Norbornadiene

Norbornadiene (Problem 14-55) can be prepared by reaction of chloroethylene with 1,3-cyclopentadiene, followed by treatment of the product with sodium ethoxide. Write the overall scheme, and identify the two kinds of reactions.

The triene shown here reacts with 2 equivalents of maleic anhydride to yield a product with the formula C17H16O6. Predict a structure for the product. O O + 2 O C17H16O6 C CH2 H CH2

Myrcene, C10H16, is found in oil of bay leaves and is isomeric with b-ocimene (Problem 14-50). It has an ultraviolet absorption at 226 nm and can be catalytically hydrogenated to yield 2,6-dimethyloctane. On ozonolysis followed by zinc/acetic acid treatment, myrcene yields formaldehyde, acetone, and 2-oxopentanedial: HCCH2CH2C O O O CH 2-Oxopentanedial Propose a structure for myrcene, and write the reactions, showing starting material and products.

Hydrocarbon A, C10H14, has a UV absorption at lmax 5 236 nm and gives hydrocarbon B, C10H18, on catalytic hydrogenation. Ozonolysis of A, followed by zinc/acetic acid treatment, yields the following diketo dialdehyde: HCCH2CH2CH2C O O O CCH2CH2CH2CH O (a) Propose two possible structures for A. (b) Hydrocarbon A reacts with maleic anhydride to yield a DielsAlder adduct. Which of your structures for A is correct? (c) Write the reactions, showing the starting material and products.

Adiponitrile, a starting material used in the manufacture of nylon, can be prepared in three steps from 1,3-butadiene. How would you carry out this synthesis? Adiponitrile H2C CHCH CH2 N CCH2CH2CH2CH2C 3 steps N

Ergosterol, a precursor of vitamin D, has lmax 5 282 nm and molar absorptivity e 5 11,900. What is the concentration of ergosterol in a solution whose absorbance A 5 0.065 with a sample pathlength l 5 1.00 cm? Ergosterol (C28H44O) HO CH3 CH3 H H H H

Dimethyl butynedioate undergoes a DielsAlder reaction with (2E,4E)- 2,4-hexadiene. Show the structure and stereochemistry of the product. CH3OC O C C O COCH3 Dimethyl butynedioate

Dimethyl butynedioate also undergoes a DielsAlder reaction with (2E,4Z)-2,4-hexadiene, but the stereochemistry of the product is different from that of the (2E,4E) isomer (Problem 14-62). Explain.

How would you carry out the following synthesis (more than one step is required)? What stereochemical relationship between the ]CO2CH3 group attached to the cyclohexane ring and the ]CHO groups would your synthesis produce? CO2CH3 + ? H CO2CH3 CHOH CHOH

The double bond of an enamine (alkene 1 amine) is much more nucleophilic than a typical alkene double bond. Assuming that the nitrogen atom in an enamine is sp2-hybridized, draw an orbital picture of an enamine, and explain why the double bond is electron-rich. An enamine C C N R R

Benzene has an ultraviolet absorption at lmax 5 204 nm, and paratoluidine has lmax 5 235 nm. How do you account for this difference? Benzene (max = 204 nm) p-Toluidine (max = 235 nm) H3C NH2

Why would medicinal chemists now find it more promising to use PDT photosensitizers based on the phthalocyanine core instead of the porphyrin core? (a) Phthalocyanine is more conjugated and therefore lmax is red-shifted. (b) Phthalocyanine is more conjugated and therefore lmax is blue-shifted (c) Phthalocyanine is aromatic and porphyrins are not. (d) Porphyrins are aromatic and phthalocyanine is not.

Phthalocyanine in solution absorbs light at wavelengths above 650 nm. What color would you expect it to have? (a) Red (b) Orange (c) Yellow (d) Green-blue

How many p molecular orbitals are present in the phthalocyanine ring? (a) 19 (b) 38 (c) 18 (d) 36

An increase in conjugation is correlated with _______ in the energy of the LUMO, _______ in the energy of the HOMO, and _______ in lmax, which results in a _______ . (a) a decrease, an increase, a decrease, red shift (b) a decrease, an increase, an increase, red shift (c) an increase, a decrease, a decrease, red shift (d) an increase, a decrease, an increase, blue shift

What if no ionic solids were soluble in water? How would this affect the way reactions occur in aqueous solutions?

Calculate the molarity of a solution prepared by dissolving 11.5 g of solid NaOH in enough water to make 1.50 L of solution.

Calculate the molarity of a solution prepared by dissolving 1.56 g of gaseous HCl in enough water to make 26.8 mL of solution.

Give the concentration of each type of ion in the following solutions: a. 0.50 M Co(NO3)2 b. 1 M Fe(ClO4)3

Calculate the number of moles of Cl2 ions in 1.75 L of 1.0 3 1023 M ZnCl2.

Typical blood serum is about 0.14 M NaCl. What volume of blood contains 1.0 mg of NaCl?

To analyze the alcohol content of a certain wine, a chemist needs 1.00 L of an aqueous 0.200-M K2Cr2O7 (potassium dichromate) solution. How much solid K2Cr2O7 must be weighed out to make this solution?

What volume of 16 M sulfuric acid must be used to prepare 1.5 L of a 0.10-M H2SO4 solution?

Using the solubility rules in Table 4.1, predict what will happen when the following pairs of solutions are mixed. a. KNO3(aq) and BaCl2(aq) b. Na2SO4(aq) and Pb(NO3)2(aq) c. KOH(aq) and Fe(NO3)3(aq)

For each of the following reactions, write the formula equation, the complete ionic equation, and the net ionic equation. a. Aqueous potassium chloride is added to aqueous silver nitrate to form a silver chloride precipitate plus aqueous potassium nitrate. b. Aqueous potassium hydroxide is mixed with aqueous iron(III) nitrate to form a precipitate of iron(III) hydroxide and aqueous potassium nitrate.

What if all ionic solids were soluble in water? How would this affect stoichiometry calculations for reactions in aqueous solution?

Calculate the mass of solid NaCl that must be added to 1.50 L of a 0.100-M AgNO3 solution to precipitate all the Ag1 ions in the form of AgCl.

When aqueous solutions of Na2SO4 and Pb(NO3)2 are mixed, PbSO4 precipitates. Calculate the mass of PbSO4 formed when 1.25 L of 0.0500 M Pb(NO3)2 and 2.00 L of 0.0250 M Na2SO4 are mixed.

What volume of a 0.100-M HCl solution is needed to neutralize 25.0 mL of 0.350 M NaOH?

In a certain experiment, 28.0 mL of 0.250 M HNO3 and 53.0 mL of 0.320 M KOH are mixed. What is the concentration of H1 or OH2 ions in excess after the reaction goes to completion?

A student carries out an experiment to standardize (determine the exact concentration of) a sodium hydroxide solution. To do this, the student weighs out a 1.3009-g sample of potassium hydrogen phthalate (KHC8H4O4, often abbreviated KHP). KHP (molar mass 204.22 g/mol) has one acidic hydrogen. The student dissolves the KHP in distilled water, adds phenolphthalein as an indicator, and titrates the resulting solution with the sodium hydroxide solution to the phenolphthalein endpoint. The difference between the final and initial buret readings indicates that 41.20 mL of the sodium hydroxide solution is required to react exactly with the 1.3009 g KHP. Calculate the concentration of the sodium hydroxide solution.

In Example 4.14 you determined the concentration of an aqueous solution of NaOH using phenolphthalein as an indicator. What if you used an indicator for which the endpoint of the titration occurs after the equivalence point? How would this affect your calculated concentration of NaOH?

If pure vitamin A has \(\lambda_{\max }=325(\varepsilon=50,100)\), what is the vitamin A concentration in a sample whose absorbance at \(325 \mathrm{~nm}\) is \(A=0.735\) in a cell with a pathlength of \(1.00 \mathrm{~cm}\) ?

What if the oxidation state for oxygen was defined as 21 instead of 22? What effect, if any, would it have on the oxidation state of hydrogen?

Assign oxidation states to all atoms in the following. a. CO2 b. SF6 c. NO3

Metallurgy, the process of producing a metal from its ore, always involves oxidation reduction reactions. In the metallurgy of galena (PbS), the principal lead-containing ore, the first step is the conversion of lead sulfide to its oxide (a process called roasting): 2PbS1s2 1 3O2 1g2 h 2PbO1s2 1 2SO2 1g2 The oxide is then treated with carbon monoxide to produce the free metal: PbO1s2 1 CO1g2 h Pb1s2 1 CO2 1g2 For each reaction, identify the atoms that are oxidized and reduced, and specify the oxidizing and reducing agents.

Dalton believed that atoms were indivisible. Thomson and Rutherford helped to show that this was not true. What if atoms were indivisible? How would this affect the types of reactions you have learned about in this chapter?

Balance the reaction between solid lead(II) oxide and ammonia gas to produce nitrogen gas, liquid water, and solid lead.

The (aq) designation listed after a solute indicates the process of hydration. Using KBr(aq) and C2H5OH(aq) as your examples, explain the process of hydration for soluble ionic compounds and for soluble covalent compounds

Characterize strong electrolytes versus weak electrolytes versus nonelectrolytes. Give examples of each. How do you experimentally determine whether a soluble substance is a strong electrolyte, weak electrolyte, or nonelectrolyte?

Distinguish between the terms slightly soluble and weak electrolyte.

Molarity is a conversion factor relating moles of solute in solution to the volume of the solution. How does one use molarity as a conversion factor to convert from moles of solute to volume of solution, and from volume of solution to moles of solute present?

What is a dilution? What stays constant in a dilution? Explain why the equation M1V1 5 M2V2 works for dilution problems.

When the following beakers are mixed, draw a molecular-level representation of the product mixture (see Fig. 4.17).

Differentiate between the formula equation, the complete ionic equation, and the net ionic equation. For each reaction in Question 6, write all three balanced equations.

What is an acidbase reaction? Strong bases are soluble ionic compounds that contain the hydroxide ion. List the strong bases. When a strong base reacts with an acid, what is always produced? Explain the terms titration, stoichiometric point, neutralization, and standardization.

Define the terms oxidation, reduction, oxidizing agent, and reducing agent. Given a chemical reaction, how can you tell if it is a redox reaction?

Consider the steps involved in balancing oxidation reduction reactions by using oxidation states. The key to the oxidation states method is to equalize the electrons lost by the species oxidized with the electrons gained by the species reduced. First of all, how do you recognize what is oxidized and what is reduced? Second, how do you balance the electrons lost with the electrons gained? Once the electrons are balanced, what else is needed to balance the oxidationreduction reaction?

Assume you have a highly magnified view of a solution of HCl that allows you to see the HCl. Draw this magnified view. If you dropped in a piece of magnesium, the magnesium would disappear and hydrogen gas would be released. Represent this change using symbols for the elements, and write out the balanced equation

You have a solution of table salt in water. What happens to the salt concentration (increases, decreases, or stays the same) as the solution boils? Draw pictures to explain your answer.

You have a sugar solution (solution A) with concentration x. You pour one-fourth of this solution into a beaker, and add an equivalent volume of water (solution B). a. What is the ratio of sugar in solutions A and B? b. Compare the volumes of solutions A and B. c. What is the ratio of the concentrations of sugar in solutions A and B?

You add an aqueous solution of lead nitrate to an aqueous solution of potassium iodide. Draw highly magnified views of each solution individually, and the mixed solution, including any product that forms. Write the balanced equation for the reaction

Order the following molecules from lowest to highest oxidation state of the nitrogen atom: HNO3, NH4Cl, N2O, NO2, NaNO2.

Why is it that when something gains electrons, it is said to be reduced? What is being reduced?

Consider separate aqueous solutions of HCl and H2SO4 with the same molar concentrations. You wish to neutralize an aqueous solution of NaOH. For which acid solution would you need to add more volume (in milliliters) to neutralize the base? a. the HCl solution b. the H2SO4 solution c. You need to know the acid concentrations to answer this question. d. You need to know the volume and concentration of the NaOH solution to answer this question. e. c and d Explain

Draw molecular-level pictures to differentiate between concentrated and dilute solutions.

You need to make 150.0 mL of a 0.10-M NaCl solution. You have solid NaCl, and your lab partner has a 2.5-M NaCl solution. Explain how you each make the 0.10-M NaCl solution.

The exposed electrodes of a light bulb are placed in a solution of H2SO4 in an electrical circuit such that the light bulb is glowing. You add a dilute salt solution, and the bulb dims. Which of the following could be the salt in the solution? a. Ba(NO3)2 c. K2SO4 b. NaNO3 d. Ca(NO3)2 Justify your choices. For those you did not choose, explain why they are incorrect.

You have two solutions of chemical A. To determine which has the highest concentration of A (molarity), which of the following must you know (there may be more than one answer)? a. the mass in grams of A in each solution b. the molar mass of A c. the volume of water added to each solution d. the total volume of the solution Explain

Which of the following must be known to calculate the molarity of a salt solution (there may be more than one answer)? a. the mass of salt added b. the molar mass of the salt c. the volume of water added d. the total volume of the solution Explain

Differentiate between what happens when the following are added to water. a. polar solute versus nonpolar solute b. KF versus C6H12O6 c. RbCl versus AgCl d. HNO3 versus CO

A typical solution used in general chemistry laboratories is 3.0 M HCl. Describe, in detail, the composition of 2.0 L of a 3.0-M HCl solution. How would 2.0 L of a 3.0-M HC2H3O2 solution differ from the same quantity of the HCl solution?

Which of the following statements is(are) true? For the false statements, correct them. a. A concentrated solution in water will always contain a strong or weak electrolyte. b. A strong electrolyte will break up into ions when dissolved in water. c. An acid is a strong electrolyte. d. All ionic compounds are strong electrolytes in water

A student wants to prepare 1.00 L of a 1.00-M solution of NaOH (molar mass 5 40.00 g/mol). If solid NaOH is available, how would the student prepare this solution? If 2.00 M NaOH is available, how would the student prepare the solution? To help ensure three significant figures in the NaOH molarity, to how many significant figures should the volumes and mass be determined?

List the formulas of three soluble bromide salts and three insoluble bromide salts. Do the same exercise for sulfate salts, hydroxide salts, and phosphate salts (list three soluble salts and three insoluble salts). List the formulas for six insoluble Pb21 salts and one soluble Pb21 salt

When 1.0 mole of solid lead nitrate is added to 2.0 moles of aqueous potassium iodide, a yellow precipitate forms. After the precipitate settles to the bottom, does the solution above the precipitate conduct electricity? Explain. Write the complete ionic equation to help you answer this question.

What is an acid and what is a base? An acidbase reaction is sometimes called a proton-transfer reaction. Explain.

A student had 1.00 L of a 1.00-M acid solution. Much to the surprise of the student, it took 2.00 L of 1.00 M NaOH solution to react completely with the acid. Explain why it took twice as much NaOH to react with all of the acid. In a different experiment, a student had 10.0 mL of 0.020 M HCl. Again, much to the surprise of the student, it took only 5.00 mL of 0.020 M strong base to react completely with the HCl. Explain why it took only half as much strong base to react with all of the HCl.

Differentiate between the following terms. a. species reduced versus the reducing agent b. species oxidized versus the oxidizing agent c. oxidation state versus actual charge

How does one balance redox reactions by the oxidation states method?

Show how each of the following strong electrolytes breaks up into its component ions upon dissolving in water by drawing molecular-level pictures. a. NaBr f. FeSO4 b. MgCl2 g. KMnO4 c. Al(NO3)3 h. HClO4 d. (NH4)2SO4 i. NH4C2H3O2 (ammonium acetate) e. NaOH

Match each name below with the following microscopic pictures of that compound in aqueous solution. + + + + + + + 2+ 2+ 2+ 2+ 2 2 2 2 i. ii. iii. iv. a. barium nitrate c. potassium carbonate b. sodium chloride d. magnesium sulfate Which picture best represents HNO3(aq)? Why arent any of the pictures a good representation of HC2H3O2(aq)?

Calcium chloride is a strong electrolyte and is used to salt streets in the winter to melt ice and snow. Write a reaction to show how this substance breaks apart when it dissolves in water.

Commercial cold packs and hot packs are available for treating athletic injuries. Both types contain a pouch of water and a dry chemical. When the pack is struck, the pouch of water breaks, dissolving the chemical, and the solution becomes either hot or cold. Many hot packs use magnesium sulfate, and many cold packs use ammonium nitrate. Write reactions to show how these strong electrolytes break apart when they dissolve in water.

Calculate the molarity of each of these solutions. a. A 5.623-g sample of NaHCO3 is dissolved in enough water to make 250.0 mL of solution. b. A 184.6-mg sample of K2Cr2O7 is dissolved in enough water to make 500.0 mL of solution. c. A 0.1025-g sample of copper metal is dissolved in 35 mL of concentrated HNO3 to form Cu21 ions and then water is added to make a total volume of 200.0 mL. (Calculate the molarity of Cu21.)

A solution of ethanol (C2H5OH) in water is prepared by dissolving 75.0 mL of ethanol (density 5 0.79 g/cm3 ) in enough water to make 250.0 mL of solution. What is the molarity of the ethanol in this solution?

Calculate the concentration of all ions present in each of the following solutions of strong electrolytes. a. 0.100 mole of Ca(NO3)2 in 100.0 mL of solution b. 2.5 moles of Na2SO4 in 1.25 L of solution c. 5.00 g of NH4Cl in 500.0 mL of solution d. 1.00 g K3PO4 in 250.0 mL of solution

Calculate the concentration of all ions present in each of the following solutions of strong electrolytes. a. 0.0200 mole of sodium phosphate in 10.0 mL of solution b. 0.300 mole of barium nitrate in 600.0 mL of solution c. 1.00 g of potassium chloride in 0.500 L of solution d. 132 g of ammonium sulfate in 1.50 L of solution

Which of the following solutions of strong electrolytes contains the largest number of moles of chloride ions: 100.0 mL of 0.30 M AlCl3, 50.0 mL of 0.60 M MgCl2, or 200.0 mL of 0.40 M NaCl?

Which of the following solutions of strong electrolytes contains the largest number of ions: 100.0 mL of 0.100 M NaOH, 50.0 mL of 0.200 M BaCl2, or 75.0 mL of 0.150 M Na3PO4?

What mass of NaOH is contained in 250.0 mL of a 0.400 M sodium hydroxide solution?

If 10. g of AgNO3 is available, what volume of 0.25 M AgNO3 solution can be prepared?

Describe how you would prepare 2.00 L of each of the following solutions. a. 0.250 M NaOH from solid NaOH b. 0.250 M NaOH from 1.00 M NaOH stock solution c. 0.100 M K2CrO4 from solid K2CrO4 d. 0.100 M K2CrO4 from 1.75 M K2CrO4 stock solution

How would you prepare 1.00 L of a 0.50-M solution of each of the following? a. H2SO4 from concentrated (18 M) sulfuric acid b. HCl from concentrated (12 M) reagent c. NiCl2 from the salt NiCl2 ? 6H2O d. HNO3 from concentrated (16 M) reagent e. Sodium carbonate from the pure solid

A solution is prepared by dissolving 10.8 g ammonium sulfate in enough water to make 100.0 mL of stock solution. A 10.00-mL sample of this stock solution is added to 50.00 mL of water. Calculate the concentration of ammonium ions and sulfate ions in the final solution.

A solution was prepared by mixing 50.00 mL of 0.100 M HNO3 and 100.00 mL of 0.200 M HNO3. Calculate the molarity of the final solution of nitric acid.

Calculate the sodium ion concentration when 70.0 mL of 3.0 M sodium carbonate is added to 30.0 mL of 1.0 M sodium bicarbonate.

Suppose 50.0 mL of 0.250 M CoCl2 solution is added to 25.0 mL of 0.350 M NiCl2 solution. Calculate the concentration, in moles per liter, of each of the ions present after mixing. Assume that the volumes are additive.

A standard solution is prepared for the analysis of fluoxymesterone (C20H29FO3), an anabolic steroid. A stock solution is first prepared by dissolving 10.0 mg of fluoxymesterone in enough water to give a total volume of 500.0 mL. A 100.0-mL aliquot (portion) of this solution is diluted to a final volume of 100.0 mL. Calculate the concentration of the final solution in terms of molarity

A stock solution containing Mn21 ions was prepared by dissolving 1.584 g pure manganese metal in nitric acid and diluting to a final volume of 1.000 L. The following solutions were then prepared by dilution: For solution A, 50.00 mL of stock solution was diluted to 1000.0 mL. For solution B, 10.00 mL of solution A was diluted to 250.0 mL. For solution C, 10.00 mL of solution B was diluted to 500.0 mL. Calculate the concentrations of the stock solution and solutions A, B, and C.

On the basis of the general solubility rules given in Table 4.1, predict which of the following substances are likely to be soluble in water. a. aluminum nitrate b. magnesium chloride c. rubidium sulfate d. nickel(II) hydroxide e. lead(II) sulfide f. magnesium hydroxide g. iron(III) phosphate

On the basis of the general solubility rules given in Table 4.1, predict which of the following substances are likely to be soluble in water. a. zinc chloride b. lead(II) nitrate c. lead(II) sulfate d. sodium iodide e. cobalt(III) sulfide f. chromium(III) hydroxide g. magnesium carbonate h. ammonium carbonate

When the following solutions are mixed together, what precipitate (if any) will form? a. FeSO4(aq) 1 KCl(aq) b. Al(NO3)3(aq) 1 Ba(OH)2(aq) c. CaCl2(aq) 1 Na2SO4(aq) d. K2S(aq) 1 Ni(NO3)2(aq)

When the following solutions are mixed together, what precipitate (if any) will form? a. Hg2(NO3)2(aq) 1 CuSO4(aq) b. Ni(NO3)2(aq) 1 CaCl2(aq) c. K2CO3(aq) 1 MgI2(aq) d. Na2CrO4(aq) 1 AlBr3(aq)

For the reactions in Exercise 45, write the balanced formula equation, complete ionic equation, and net ionic equation. If no precipitate forms, write No reaction.

For the reactions in Exercise 46, write the balanced formula equation, complete ionic equation, and net ionic equation. If no precipitate forms, write No reaction.

Write the balanced formula and net ionic equation for the reaction that occurs when the contents of the two beakers are added together. What colors represent the spectator ions in each reaction? + Cu2+ SO4 2 Na+ S2 a. + Co2+ Cl Na+ OH b. + Ag+ NO3 K+ I

Give an example how each of the following insoluble ionic compounds could be produced using a precipitation reaction. Write the balanced formula equation for each reaction. a. Fe(OH)3(s) c. PbSO4(s) b. Hg2Cl2(s) d. BaCrO4(s)

Write net ionic equations for the reaction, if any, that occurs when aqueous solutions of the following are mixed. a. ammonium sulfate and barium nitrate b. lead(II) nitrate and sodium chloride c. sodium phosphate and potassium nitrate d. sodium bromide and rubidium chloride e. copper(II) chloride and sodium hydroxide

Write net ionic equations for the reaction, if any, that occurs when aqueous solutions of the following are mixed. a. chromium(III) chloride and sodium hydroxide b. silver nitrate and ammonium carbonate c. copper(II) sulfate and mercury(I) nitrate d. strontium nitrate and potassium iodide

Separate samples of a solution of an unknown soluble ionic compound are treated with KCl, Na2SO4, and NaOH. A precipitate forms only when Na2SO4 is added. Which cations could be present in the unknown soluble ionic compound?

A sample may contain any or all of the following ions: Hg2 21, Ba21, and Mn21. a. No precipitate formed when an aqueous solution of NaCl was added to the sample solution. b. No precipitate formed when an aqueous solution of Na2SO4 was added to the sample solution. c. A precipitate formed when the sample solution was made basic with NaOH. Which ion or ions are present in the sample solution?

What mass of Na2CrO4 is required to precipitate all of the silver ions from 75.0 mL of a 0.100-M solution of AgNO3?

What volume of 0.100 M Na3PO4 is required to precipitate all the lead(II) ions from 150.0 mL of 0.250 M Pb(NO3)2?

What mass of solid aluminum hydroxide can be produced when 50.0 mL of 0.200 M Al(NO3)3 is added to 200.0 mL of 0.100 M KOH