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A) 60L.8) 0.7L.C) 1/6the original volume.D) More information is needed to answer this question.E) 6 times the original volume.

2. CS2(g) + 3C12(g) = CC14(8) + S2C12(g)At a given temperature. the reaction above is at equilibrium when [CS2] = 0.050 A4, [C12] = 0.25 A4,

[CC14] = 0.15 A4. and [S2C12] = 0.35 j'}'4. What will be the direction of the reaction when thereactants and products have the following concentrations: CS2 = 0.15 jly/. C12 = 0.21 A41, CC14 = 0.29

tly4, and S2C12 = 0.34 Jt4?

A) totheleft8) {otherightC) nochangeD) cannot predict unless we know the temperatureE) cannot predict unless we know whether the reaction is endothermic or exothermic

The reaction of Hcl with NaoH is represented by the equation

HC1(c7q) + NaoH(c7g) i Nacl(czq) + H20(/)

What volume of 0.631 iL{/ HC] is required to titrate 15.8 mL of 0.321 A4NaoH?A) 3.20mL8) 1.58mLC) 8.04mLD) 15.8mlJ

E) 3l.1mL

4. IfKc. = 0.145 for A2 + 28 = 2AB, what is the value ofKc` for the reaction

4AB = 2A2 + 48?

X0112SPG17 -Solutions, Kinetics & Equilibrium

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r.`H3#t/-',,

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5. A student must prepare 5.00 L of o.100 A4Na2C03 (106 g/mol). Which is the best procedure for

preparing this solution?A) Measure 53.0 g Na2C03 and add 5.00 kg of I-120.8) Measure 10.6 gNa2C03 and add 5.00kgofH20.C) Measure 53.0 g Na2C03 and add H20 until the final homogeneous solution has a

volume of 5.00 L.D) Measure 10.6 g Na2C03 and add H20 until the final homogeneous solution has a

volume of 5.00 L.E) Measure 53.OgNa2C03 andadd 5.00LofH20.

6. For the reaction Br2(g) + C12(g) = 2Brcl(g), at equilibrium, it is found that the concentrations

of Br2. C12, and Brcl are 0.398 /t4. 0.351 +fy4, and 2.05 x 10-3 A4, respectively. What is the value of

A) 3.0] x 10-5

8) 1.20xl0-+

C) 1.47x|0-2

D) 6.81 x 10'

E) 3.32x|o4

7. For the first-order reaction

1 /2 N204(g) i N02(g); AfJ = 28.6 kJ

the rate constant is fr = 9.29 x 10+ s-I at ~20°C. and the activation energy is 53.7 kJ/mol. What isthe rate constant at 21 °C?

A) 1.08x|05s`~1

8) 9.29x|04s-I

C) 1.74x|05s+

D) 3.27x|06s-I

E) 4.94x|04sl

8. At 298 K, the value of Kc for the reaction H2(g) + Br2(g) = 2HBr(g) is 2.0 x 10!9. What is Kc,

for HBr(g) = 1/2112(g) + 1/2Br2(g)?

A) 4.Ox 10-38

8) 5.Oxl0-20

C) 1.Oxl019

D) -2.Oxl019

E) 2.2xl0-IO

X0l 12SPG17 -Solutions, Kinetics & Equilibrium

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ID:C

9. The nuclide 96Nb decays by a first-order process with a rate constant of 2.96 x 10-2 h-I. How longwill it take for 82.0% of the initial amount of 96Nb to be consumed?A) 33.8h

8) 57.9hC) 27.7hD) 6.70hE) 6.08h

10. Consider the reaction

c7A + 6B ± c7D + eE C = catalvst

The rate law is

Rate = fr[A]q[B]r[C.F

Which of the following statements is incorrect?A) The exponents g and 7'. are always equal to the coefficients c7 and b, respectively.8) The overall reaction order is q + ;. + j{.C) The exponent s must be determined experimentally.D) The symibol k represents the rate constant.E) The exponents c/. ;', and s ai.e often integers.

11. Nitrosyl chloride is produced from the reaction of nitrogen monoxide and chlorine:

2NO(g) + C12(g) i 2NOcl(g)

The following initial rates at a gi\ren temperature were obtained for the concentrations listed below.

Experiment Initial Rate (mol.L-I.h-I) LNO]o (moFL') [C12]o (mol.LJ)

From the data` what is the experimental rate law?A) Rate=fr[C12]

8) Rate=#[NO]C`) Rate = 4[NO][C12]2

D) Rate = frINO]2[C12]

E) Rate = frLNO][C12]l;2


12. The following data were obtained for the hypothetical reaction 2A + 8 + products.

[A]o t,ko [B]o (Jay) Initial Rate (A4/s)0.2 0.1 50.2 0.2 200.6 0.1 45

What is the overall order of this reaction?

13. For which of the following reactions will the reactant experience the largest degree ofdecomposition upon reaching equilibrium at 500 K?

¥f, 14.

2N02F(g) = 2N02(6J) + F2(g): Kp = 6.6 x 10-222S03(g) = 2S02(g) + 02(g); Kp = 1.3 x 10-5

2NOF(g) i: 2NO(g) + F2(g): K,7 = 1.2 x |0-262NOC1(g) = 2NO(g) + C12(g): Kf, = 1.7 x 10-2

2No2tg, = 2Notg, + o2tg,; Krp = 5.9 x lot

ID:C

A chemical reaction that is first-order in X is observed to have a rate constant of 2.20 x I 0-2 s-i . Ifthe initial concentration of X is 1.0 A,/, what is the concentration of X after 186 s?A) 0.20J,W

8) 0.017A4C) 64„D) 0.59Jly4

E) 0.98/W

15. For whicli of the following equilibria does Kc, = Kp?

A) N2(g) + 3H2(g) = 2NH3(g)`_,di 8) CO(g) + H20(8) = C02(8) + H2(g)

C) CO(g) + 3H2(g) ± CH4(g) + 1120(8)D) cao(L}') + co2(g) = caco3(.``)E) HBr(£J) = I/2H2(g) + I/2Br2(/)

16. For the hypothetical reaction A + 28 + 2C + D. the initial rate of disappearance ofA is 2.0 x 10-2mol/(L . s). What is the initial rate of disappearance of B?

x 10-2 mol/(L . s)

x 10-2 mol/(L . s)

x 10-1 mol/(L . s)

10J mol/(L . s)10-2 mol/(L . s)

4


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ID:C

17. Which of the following statements is true in a reaction system at equilibrium?A) The equilibrium constant is zero.8) The number of collisions per unit time between reactants is equal to the number of

collisions per unit time between products.C) Reactants are reacting to form products at the same rate as products are reacting to

form reactants.D) Reactants and products are present in equimolar amounts.E) The product of the concentrations of the products divided by the product of the

concentrations of the reactants is always a constant.

18. A 50.00-mlj sample of a weak acid is titrated with 0.0955 £fy4NaoH. At the endpoint, it is foundthat 32.56 mL of titrant was used. What was the concentration of the weak acid?A) 0.0622A/8) 3.11A4

C) 0.0955JW

D) 5.87x 10-5+/t4

E) 0.147J,W

§;'_ I 9. In a volumetric analysis experiment a solution of sodium oxalate (Na2C204) in acidic solution is---,"~-`f titrated with a solution of potassium permanganate (KMn04) according to the following balanced

chemical equation:

2KMn04(Cf9) + 8H2S04(C/9) + 5Na2C204(CZ9) ri 2Mns04(C79) + 8H200 + 10C02(g) +5Na2S04(cJg) + K2S04(fJc/)

What volume of 0.0388 A4 KMn04 is required to titrate 0.134 g of Na2C204 dissolved in 20.0 mLof solution?A) I.38mL8) 3.45mLC) 10.3mLD) 25.8mLE) 20.OmL

illiE~i6giv

X0112SPG17 -Solutions, Kinetics & Equilibrium ID:C

21. The rate constants for the first-order decomposition of a compound are 6.19 x 104 s-I at 43°C and

I- i 7 -

-i

2.71 x 10~3 s``] at 65°C. What is the value of the activation energy for this reaction?

(Zi = 8.31 J/(mol . K))A) 0.677kJ/mol8) 25.9kJ/molC) 0.558kJ/molD) 59.6kJ/molE) 1.56kJ/mol

22. Which of the following statements is true concerning the reaction given below?

2H2S(g) + 02(8) i 2S(LS') + 2H20(g)

A) The rate law is Rate = k[H2S]2[02].

8) The reaction is second-order in H2S(g) and first-order in 02(g).C) The reaction is first-order in 112S(g) and second-order in 02(g).D) The rate law is Rate = fr[H2S][02].E) The rate law may be determined only by experiment.

23. What is the molarity of an Nal solution that contains 7.3 g ofNal in 28.0 mL of solution?

#24

0.049 JW0.0038 JW

0.00019 JW

0.26 |ly4

Which of the following equilibria would be affected by volume changes at constant temperature?HC1(`c7g) + NaoH(¢g) = H20(/) + Nacl(fJg)C2Hi(8) + H2(8) = C2H6(8)2HC1(g) = H2(g) + C12(g)S03(g) + NO(6') = N02(g) + S02(g)2HF(g) = H2(g) + F2(8)

25. What mass of Na2C`03 is present in 0.650 L of a 0.505 /14Na2C03 solution?

68.9 953.5 9

1369

82-3 g


26. What mass of H3P04 (98.0 g/mol) is present in 36.2 L of a 0.0827 twsolution of H3P04?A) 0.0305g8) 0.00341g

C) 2.93x|o2g

D) 4.29x |o4gE) 4.479

27. A 4.50-mol sample of HI is placed in a 1.00-L vessel at 460°C, and the reaction system is allowedto come to equilibrium. The HI partially decomposes, forming 0.343 mol H2 and 0.343 mol 12 atequilibrium. What is the equilibrium constant Kc for the following reaction at 460°C?

1/2 H2(g) + 1/212(g) = HI(g)

A) 1.23x|o2

8) 8.10x|o~3

C) 3.09x|o-2

D) 11.1

E) 5.69

What volume of 2.52 A4 Hcl is required to prepare 176.5 mL of 0.449 A4 Hcl?

A) 9.91 x 102mL

I.56 x 102 mL

31.4 mL

0.0318 mL

2.00 x 102 mL

How many moles of sulfate ions are there in a 0.545-L solution of 0.489114 A12(S04)3?0.267 mol0.800 mol3.34 mol0.0888 mol2.69 mol


30. Which of the following conclusions concerning the concentration-time plot provided below is/arecorrect?

1. The concentration of substance D is decreasing over time.2. The instantaneous reaction rate at point A is less than the instantaneous

reaction rate at point 8.3. Substance D is a product of the reaction.

A 8

Time (s) -A) 1on]y8) 2onlyC) 3onlyD) 1and2E) 1,2,and3

31. For the reaction of the ammonium ion with nitrous acid. the net reaction is

NH4+(cJg) + HN02(cZ¢) i N2(g) + 2H20(/) + H+(f/g)

If the initial concentration of nitrous acid is 1.00 .Iy/ and, after 28.8 s has elapsed, the concentrationof nitrous acid has fallen to 0.82 [W, what is the average rate of the reaction over this time interval?A) 0.0063 J14/s

8) 0.028 Jly,/,'S

C) -0.0063 Jly4/s

D) ~0.028A4/sE) 0.063 I,},A/s

32. At a given temperature, a first-order reaction has a rate constant of 3.5 x 10~3 s-1. How long will ittake for the reaction to be 24% complete?A) 410sa) 1200sC) 910s

D) 34sE) 78s

8

X0l 12SPG17 -Solutions, Kinetics & Equilibrium

The half-life of a reaction is

E)

i,,.,-.,::,'

twice as long for a second-order reaction as it is for a first-order reaction.one-half of the time the reaction will take to go to completion.how long the reaction can run before stopping.the time it takes for the amount of product formed to equal half the initial amountofreactant.the time it takes for the reactant concentration to decrease to one-half of its initialvalue.

ID:C

34. A dilute solution is prepared by transferring 45.00 mL of a 0.5616 M stock solution to a 400.0 mLvolumetric flask and diluting to mark. What is the molarity of this dilute solution?

A) 0.06318jfy{/

8) 0.1264jwC) 0.04992 ily4D) 0.0158011,4

E) o.28o8JW

The Ostwald process converts ammonia (NH3) to nitric oxide (NO) by reaction with oxygen in the

presence of a catalyst at high temperatures. In a test of the process a reaction vessel is initiallycharged with 3.90 mol NH3(g) and 4.90 mol 02(g), sealed, and heated at a fixed high temperature.When equilibriuni is established the reaction mixture is analyzed and found to contain 2.90 molNO(g). What is the quantity of NH3(iJ) in the equilibrium reaction mixture?

4NH3(g) + 5o2(g) = 4No(g) + 6H2o(`€r)

A) 1.00mol NI|3(g)

8) 6.80molNH3(g)

C) 3.90molNH3(g)

D) 1.28molNH3(g)

E) 2.00molNH3(g)

36. For a certain first-order reaction with the general form CZA + products. the rate is 0.32 jly/.s~] whenthe concentration of the reactant is 0.29 ,W. What is the rate constant for this reaction?


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ID:C

37. When the concentrations of the reactants are increased, the rate of the reaction increases. This isbest explained byA) an increase in the fraction of molecules that have enough energy to react.8) an increase in the rate constant.C) an increase in the average potential energy of the molecules.D) an increase in the frequency of the molecular collisions.E) an increase in the kinetic energy of the molecules.

L&::i 38. What minimum mass of copper (II) nitrate must be added to 30.0 mL ofa o.0387 jlytphosphatesolution in order to completely precipitate all of the phosphate as solid copper (11) phosphate?

2P043-(c/g) + 3Cu(N03)2(4Jg) i Cu3(P04)2(j`) + 6N03~(CJ9)

rfty¢7%

39. Which of the following equilibria would flQ± be affected by pressure changes at constanttemperature?A) C02(g) + H2(g) = CO(g) + H20(g)

8) CO(g)+£02(8) = C02(g)

C) 2Hg(f) + 02(g) = 2Hgo(L`i)D) 2H2(g) + 02(g) = 2H20(DE) caco3(s) = cao(5y)+co2(8)

-ffS ifl.

A first-order chemical reaction is observed to have a rate constant of 25 mini . What is thecorrespondiiig half-life for the reaction?

1.7 min

36 min2.4s35.8 s

For the hypothetical first-order reaction A i products. fr = 0.0839 s-i. If the initial concentrationof A is 0.640 jw. how long would it take for. A to be 66.4% consumed?A) 8.26s8) 13.Os

C) 11.9s

D) 18.6s

E) 4.88s

10


42. For the formation of 1 mol of nitrosyl chloride at a given temperature, Af7 = 44 kJ.

Z)43

C1

ID:C

NO(g) + 1/2 C12(g) i NOcl(g)

The activation energy for this reaction is 59 kJ/mol. What is the activation energy for the reversereaction?A) 59kJ/mol8) 15kJ/molC) 103kJ/molD) 44kJ/molE) -103kJ/mol

Which of the following correctly describes the equilibrium constant for the gas-phase reactionbetween H2 and 02 to foml gaseous H20?

A)Kc

B)Kl

[H2 ][02 ]

[Hjo]

[H2CJ]

[H2 ][C)2 ]

C) Kf =[H20]

D)K:

E)K

[H2C,,]2

[H2t.J]2

[H2][L12]

44. The following reaction is investigated (assume an ideal gas mixture):

2N20(g) + N2H(g) = 3N2(g) + 2H20(g)

Initially there are 0.loo mol ofN20 and 0.25 mol of N2H4. in a 1 0.0-L container. I-f there are0.062 mol ofN20 at equilibrium, how many moles of N2 are present at equilibrium?A) 3.8x|o~2

8) 1.1xl0-I

C) 5.7x|o-2

D) 1.9x|o-2

E) noneofthese

11


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ID:C

45. Consider the following equilibrium:

PC13(g) + C12(g) = PC15(g); Df7 = -92 kJ

The concentration of PC13 at equilibrium may be increased byA) decreasing the temperature.8) adding c12 to the system.C) adding pc15 to the system.D) increasing the pressure.E) adding a catalyst.

46. A sample of ammonia gas was allowed to come to equilibrium at 400 K.

2NH3(g) = N2(g) + 3H2(g)

At equilibrium. it was found that the concentration of H2 was 0.0367 il41, the concentration of N2was 0.0122 A{/, and the concentration of NH3 was 0.170 jJL4. What was the initial concentration ofammonia?A) 0.122Jly4

8) 0.146lMC) 0.218A4

D) 0.182JW

E) 0.194A4

47. In a first-order reaction, the half-life is 137 minutes. What is the rate constant?A) 1.22xl04s-I8) 5790s-1C) 0.304s-1

D) 5.06 x 10-3 slE) 8.43xl0-5s+

48. The following data were obtained in a kinetics study of the hypothetical reaction A + 8 + C +

I- z £4lii! products.[AloJjl4l [BloJ44l [£JOJ44 Initial Rate (10-3L!4!s}

0.4 0.4 0.20.2 0.4 0.40.6 0.1 0.2

0.2 0.1 0.2

0.2 0.2 0.4

160

8015

520

Using the initial-rate method, what is the order of the reaction with respect to A?A) first-order8) zero-orderC) third-orderD) second-orderE) impossible to tell from the data given

12


49

ID:C

The concentration of Pb2-I in a sample of wastewater is to be determined by using gravimetricanalysis. To a 100.0-mL sample of the wastewater is added an excess of sodium carbonate.forming the insoluble lead (11) carbonate (267.2092 g/mol) according to the balanced equation

given below. The solid lead (11) carbonate is dried. and its mass is measured to be 0.4078 g. Whatwas the concentration of Pb2+ in the original wastewater sample?

Pb2+(c7g) + Na2C03(cJg) i Pbc03(s.) + 2Na+(cJ(/)

0.01526 |ly/

0.001526 /W1.090 A4

0.004078 lly/65.52)2M

If a reaction is zero-order in a reactant, when the concentration of the reactant is decreased by afactor of 2. the reaction rate will

quadruple.decrease by a factor of 1/2.remain constant.decrease by a factor of I /4.double.

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