1. A gas absoi;bs 0.0 J of heat and theif performs'56.8 J of work. What is the change in internafenergy of the gas? A) 16.8 J " ^ ^ ^ ^ ^ B) 56.4 J

7 y C) 96J J c.-<PT

E) none of these . ^ c: - 3

2. For a particular process, q = +20 kJ with m - = 15 kJ compression. Which of the following statements is true? » — — - . ^ A) Fleat flows from the system to the suiTOundings. /(,f^''

C B) The system does work on the surroundings. ' c

D) ~^tt-crrtH(raBove are true. C' / „ , ~, E) None of the above are true. 6*-^^ ^^J'^^^^T"

3. Which of the following compounds has the highest standard entropy per mole at 298 K? A) CHsOl-KO "

h tJ)" Si02(.v) / / 7 / D) H20(/) f^^' 'Pji^^"-" E) CaCOsCv) — '

4. The standard enthalpy of vaporization of Freon-13, CF3CI, is i5.65 kJ/mol at its normal boiling point o f - 8 2 ° C . What is the change of entropy for 1 mol o f Uquid Freon-13 when it vaporizes at its normal boiling point? A) 81.9 .J/K

A B) -0.191 J/K 1., ^ , (J\) -1.91 X 10 J/K ^ ^rt/yCA

D) 8.19 X 10-M/K E) 2 : 9 9 x ] 0 M / K ^ :r--f2.^(^ (^^J'yl/c)

Page I

7

5. The standard enthalpy of vaporization o f ether is 26.5 kJ/mol at its normal boihng point, 34.5°C. What is the standard change in entropy for the vaporization of ether at its normal boiling point? i^-- -J^ ' /• A) -26.5 .l/(mol • K) ^ f-f^ ^ ^ ^ ^ ^ " ^ ^ "^r O,^-^'-^ B) 0.768 J/(mol • K) _ , *^ C) 768 J/(mol • K ) , ^ 7 t f , ^T-?? ' Jq?. fh~ D) 86.1 J/(mol • K)

E) 0.086. J/(„,o, . K) p „ ^ ^ ^ ' ^ ^ , £

6. hi which reaction is AS° expected to be positive? A ) h^^W)(Ajd^~^\^ B) H20(/)-^H20(.y) ^^^-^ / C) CH30H(g) + K 02(^) -> C02(g) + 2H20(1) ^ o )

D0^2O2(^) + 2 S 0 ( . g W 2S03(.g)//y.^ / _ none of these^^^^^ ^ ' r-~s>A.-.

-.,,„ ^ ^T '' '^"^ 7. For which of the following reactions is AS" at 25°C closest to zero? )}

A) H2(g) + l2(^)->2Hl(g) V , ^ . ^ ^ - - ' " _

B) C i a M t J f l i a z t C#l4Br2(/) \. \ a / O N2(g) + 02(g) 2N0(gP~^^ M - ' ^

' ^ ^ i . . 2 N o ^ : ^ 2 g g r ^ V . ^ ^ E) CH3CH0(g) + 5/202(g) ^ 2C02(i) + 2H20(g) — J ' V

8. Fojih&mtQsj.Bj:.g)^3^^^ . x;::: CS) A / / i s + and AS'is £ f o ? t h e react^ip ^ ^ j ^ / T ^ C ) A'/h>*-> ^-J

B) AFis~^^^~aji3''ASTs - for the reaction. v _ / C) A / / i s + and AS i s - f o r the reaction. " ^ ^ (j^Cr^/JLr//<f^, D) AT/ i s - and AS is + for the reaction. /^/icrr<2<. ' /") E) AG is + for all temperatures.

9. What is AS° at 298 K for the tlillowing reaction? 203(g) -> 302(g) Substanc 5° (J/(mol • K ) U t 298 n Q

A) V l 3 7 . 4 J / K ~ ^ ) /

c) +33.8 J/K • .-^ 'rr^- ^ D) -33.8 J/K ^ r E) +443.8 J/K - ^

10. What is AG° at 298 K for the following reaction? " " , 12(g) + Cl2(g) -» 2ICl(g); A//° = -27.4 kJ; A<?° = 11.5 J/K at 298 K I ' ^ - M i l ~ ' ' ^ a * -A) -24.0 kJ ' -B) -3.45 X 10^ kJ 4^—' /^-^ - i^- ^^9- h' ^ - ^ ^ ^ " ^ 0

. , € ) - S O l k T ) / ' ^ "^"•'^

11. ^tiM19,MMi^\or\c weak acid, HA, has a pH of 4.90 at 298 K r W l i a t is AG° for the followins eqiiTtitrriurn? s. <-;: , — —

HA(ag) + H20(/) ^ H30-(flfy) + A-(«g) r..^^r- -r ,

12. For a reaction system that is at equilibriimi, which of the foll(^:^ing rtiiist aMays be true? ^ ^ A T A G ^ ! } ^

C) A f / = 0 ^ • D) A5' = 0 E) q = Q

Page 3

13. The standard free energy of formation of nitric oxide, NO, at 1000. K (roughly the temperature in an automobile engine during ignition) is 78D kJ/moI. Calculate the equilibrium constant for the reaction ~

N3(g) + 0 , ( g ) ^ 2N0(,g)

at 1000. K. (Note: The listed free energy value is for one (1) mole of ISIO(g). The

reaction equation shows 2-moles of NO(g). Therefore, A C must be doubled in

equation containing Keq... i.e.. 2( A G ) = -RT InKcq and solve for Keq.) A) 1.56 ^ 10 B) 8.42x10-5 J/^C-::, -fl'rX'- ^'s-,^ C) ,..-..1.4,7- ^ ^

C ' D ) 7.10 x i ^ c3(rt) - --•(^%rt'••V::r,^y QaN^ } .^--l'^--

14. Consider the following hypothetical reaction (at 319.0 K) . Standard free energies, in kJ/mol, are given in parentheses.

A B + C AG° = ? (-32.2) (207.8) (-237.0) -

What is the value of the equijibnumcqnstant for the reaction a^^l9.0 K? (Note: No

need to use a multiple o f A G " in this problem as detemiination of A G is a per mole valu£LasL.£a]culated.) ,-]"'"" ""i ,

C) 6.0 x i o ^ f - Z ? - 7 p ^ - ; ^ / -^-2 2 ? , : 0 / J t > " - - J D) " 73 ^ E) 0.41 4 r 4^ • • * ^ « v ^ i ^ ' V ^ - ^ " ^

15. For which of the following reactions is A//equal to AW (Note: AU is 'Internal Energy'.) A) 2 H 2 0 2 ( / ) 2 M 2 0 ( / ) + 02(g) ' B) BaO(^) + S03(g)-> BaS04(,v) 'V'- > / , "-j.yr,^--

) Q^Qigl+^Q^JE) ^ 2N02(£) ^ / f - - - ^ ^ ^ ^ ' i - ( ^ ) + c i 2 ( g ) - n H C ! ( i r : ) ^ . / I / /

Page 4

16. According to the tollovving thermochemicai equation, it 422.3 g ot N O 2 is produced, \how much heat is released at constant pressure? (Hint: CoverTgrams produced to moles - ^ and solve by proportional ratio.) , ^ ^ ^ _ ^j^,-^ 2 N O ( g ) + 0 2 f g ) - ^ 2 N G 2 ( < ? ) ; AW° = - l ] 4 . 4 k J / ' ' " ^ A) 1.050 X iO^kJ " V ,5 ,^ I f i Z i l ? / * ' r ^ / i ^ H ' i B) 12.46 kJ V r > ' ^ - ^ ^ j , -C) 5.251 X 102 kJ .'• - ' ^ , / / ^ — ' D) 114.4kJ i y i y ^ ^ ,,1 E) 4.831 X 10-1 kJ ' ""^^ , V . I

17. How much heat is gained by iron when 12.0 g of iron is wanned from 14.4°C to '] ^ 2-7 ^ ° C ? Thespecfficheatofiron i s 0 , 4 W r ( g • °C). ( A) 7 .76x10'J ' '^ ^ — B) 4.28 x 102 J % ^ '

18. A 140.0-g,sample ofmetai a(^0.0°C i i i d d e d to 140.0 g of H20(7) at 22,.a°C in an insulated container., TJie temperature rises to 23.91C- Neglecting the heat capacity o f the container, what is the specific heat of the metal? The specific heat of H->0(/) is 4.18

] < e g ) 0 . 1 4 3 j f e ° C ) ^ " ^ ^ ^ ^ 5 V •

D) 122 J/(g • °C) ^ - ' • E) 4 . 1 8 J / ( g - X ) / / f ^ 0 . ^ . f s V / - ^ £ ? ? ^ « ' ^ / ^ ^ ' / ' ^ 7 - - ^ ^ ' ^ A , . ^ 1 - . , .

19. How much heat must be applied to a 38.3-g sample of nickel {specific hecit (c) = 0.443 J/(g • °C)) m order to raise its temperatiire from 22.8°C to 378.8°C? A) 1.58 X 102 J

f D) 1.36 x l O M — / / ^ ^ T T

^ ^ ^ . ^ 7 - ^ : o 4 T | 3 p _

\

Page 5

20. In the foUovving reaction, which species is oxidiii8?~~~^-- fft-oc-jir cpu^erh"^-') X l f e S f s t ^ H X f l g ) + 2N03'(aqr^6Cs'(aq) + 3S(.v) + 2Nb(g) + 4M2O

A ) CS2S.J'-"-'^^ ^z- , . > t^^^ci.,z^

C) NO3- ^ / ' D) NO E) Cs"

21. For the reaction that occurs in a lead storage batter>', Pb(.v) + Pb0_2(£)_+2H'(f«/) + 2nmA\aq) 2PbS04(j) + 2H20(/) the oxidizinga^nfiiS A 7 P b ^ ' ' • + y > - ^ i ^ f " .-.-••*•• " „ r^^t)

B) Pb02. ^ ' ^l-^cC ^ •? H ^ ^ -'••- ••'> a i / . ^ - > K , C) H ' . D) HSO4-. E) PbS04.

4

22. When the following oxidation-reduction reaction is balanced, what is the sum of die coefficients?

P4 + CI2 - PCI5 c r ) f^fi^^s. & 0

f '4-- .

23. The following reaction occurs in basic solution. What is the sum of the lowest whole-number coel^lcienls in the balanced equation? '

Mn04^+ NFI3 -> N O 3 - + Mn02 A) 9 B) 18 C) 12

( + • 7

1 •--'-4 .ii*. • »«r»«*i W'>"

4 4 ^

3S. 0

k i i - . - ^ f . 2 K'+^f- ^

V .

. . . . / / • ; ^ / ..'

Paie 6 _ _ £ _ _ „ I _ L . ^ . _ . - -^-"<-''

24. The folJowing change occurs in ^ i d i c sdkition: S--{aq) + Cr-Oriaq) ^ ' S,{s) + Qx^\aq)

In the balanced equation, tor every mole of j ^ r i O j ; that reacts,

6 consumed. »^ ^^^^^ '""^ mol o f t r are

E ) ' i f " ' ^ )

4.-7

25. When the following oxidation-reduction reactiQn in acidic sohib©aj&.balkiicedj whatis the Iqwestjtvhole-jiun^ Na*^(cic])7) ' N a ( 5 ) + Cu2+(flg) -> Na-(o^) + Cu(.v) ^ ' C ^ ' , • • - " - " ^ - - s ^

/ ? c c S l D . . . ^ ^ ^ ^ ' - ^ G ; ^ ^ ^ ^ ^ ^ ^ ^ D) 4 E) 5

/

26. When the following oxidation-reductiqo .reaction in acidic soludon is balanced, what is \e lowest whole-number coefficient for H'^.knd on which side of the balanced equation

I should it appears ^ f^^j^^ / CriOi^-iaq) {CH20(aq)-> Cr^^aq) + HCOOHiaq)'

) ' ) A) 1, reactant side ^ . / r | B) 2, product side '--y^^.fe.l

'), product side I, reactant side 14, reactant side

/ 27. Which of the following statements is true for a voltaic_(galvanic) cell? A l The electron flow is from the positive electrode to the negative electrode.

^ 'vJt)--Jhe electron flow iTfrom the anode to the catfioder> u^^' ox<^ r"'f / C) The electron flow is from the oxidizing agent to the reducing agent dirough anr^—) ' -"^A^-

/ external circuit. D) The electron flow is from the negative cathode to the positive anode, (f f-f*,v-j H^^yf"—) f» E) The electron flow is through the salt bridge.

2-,-"7 . 0

Paae 7

28. A strip of iron is placed in a 1 M solution of iron(II) sulfate, and a .strip of copper is placed in a 1 M solution of copper(n) chloride. The two solutions tire connected with salt bridge, and the two metals are connected to a voltmeter. With the two electrodes connected together, ho\ do the,Q; ions move?

Reduction Half-Reaction £ ° (V) '/C J f^tiA^ f ^

Cvt'iaq) + 2e- ^ = Cu(.s) ^,,Al,„-tbi.ojj4ihji£,£^maIi^^

/" B) through the salt bridge from the Cu half-cell to the Fe half-cell V..__C)IIhwSi3am iasiiJon —~~ — ™ ,

D) in the direction opposite to the movement of the sulfate ions E) together with the Cu"' ions to form an insoluble precipitate

Fe(,v) -0,41

0.34

£'°ceii = 1 -66 V for the following cell reaction; P4(5) + 30maq) + 3H20(/) -> PVhig) + 3H2P02"(^i?) The o.xidizing and reducing agents are, respectively, A ) P4andOFl-. B) C) D) E)

OH- and P4. H2O and P4. P4 and H2O. P4 and P4.

0 r / c ^ i c T ^

30. A strip of iron is placed in a A'/solution of iron(ll) sulfate, and a strip GfTXS^^f^P^"^ placed in a 1 A/solution of copper(ll) chloride. The two solutions are connected with a (-7^^ salt bridge, and the two metals are connected by a wire. U.^.£A..

Reduction Half-Reaction E° (V)

2e- ^ F^'iaq)

Cu-^iaq) + 2e-

Fe(,v)

^ Cu(5)

-0.41

0.34

Which of the following takes place? A ) The Fe{II) concentration of the iron half-cell decreases, B) Chlorine is produced at the iron electrode. Cj Chlorin£ is prpdjJ^^ ^^IPP '" electrode.

Copper atoms deposit at the cathocle^ E) STitftfrttep(>sirsiimt.' iroii-Trtertrtfcre.

Page 8

31. Which of the following statements is true concerning half-cell I I of the voltaic cell shown below?

Voltmeter

1}

Zn

c r

NO,

3+ Cu

SQ 5-

n ^ 4, ^"^ff*

) f^u- migraies away rrom me u catnoae. / / * D) Cu " migrates toward the Cu cathode.-***^ /^S^*' E) There is no net migration o f Cu * tow^ard or away from the Cu electrode.

A) Cu "*" migrates away from the Cu anode. B) Cu " migi-ates toward the Cu anode. C) Cu^^ migrates away from the Cu cathode.

/I 32. According to the following cell notation, which species is undergoing oxidation?

'^IQ)\\MI\02{S)\M\R\AQ)\?\

C) Pt D) Mn02 E) Mn^^

,/ c^-''^^\{ m^cx^i a^,^^-f>*^^

.' 33. In the following electrochemical cell, what is the oxidizing agent? , ^ Ni(^) |Ni"(a^aFe^-(ag) ,Fe2>c/) |Pt (5) — - ™ ^

34. In the following electrochemical cell, what is the reducing agent? Zn(.v) I Zn^'Xaq) \\ Fc^^aq) | Pt(5) A). M

)

D) Fe2- / . ^ c ^ 5 = ^

4" J.

/"^S. A zinc-copper voltaic cell is represented as follows: Zn(^) I Zn'^(l .0 kf) 1) Cu2^(l .0 iV/)) Cu{ s j C-f ^ Which of the following statements is false? - •

J J J AX., The mass of the zinc electrode decreases dunno discharge. ifj) (B) The'coppeFelectro^^ / ^ ^T'/^ elZ i -

C) Electronslow through tfie"exfefnal circuit Irom the zinc electrode to electrode,

D) Reduction occurs at the copper electrode during discharge. ' \) The concentration of Cu^' decreases during discharge.

the copper

J

36. >'hat isthe cell reaction for the following voltaic cell? (^Cr(5) j Cr3-(«^) (i Br-(ag) ( BrzCg) I P t © >

*' A) Cr(.v) + 2Br(af/) ^==^ Br2(g) + Qx^'Uiq)

I B) 2CT^-%aq) + 6Bi-(«g) 2Cr(.v) + 3Br2(g)

C) CJ(S) + 3Br2(g) Cr3"(.v) + IBriaq)

C D ) 2 C r l » + 3Br2(g) ^ 2Cr-'-(afy) + 6 B r ( a f ] ) )

E) Cr(i') + C^aqf^^Br(aq) + Briig)

-t-i

N O , '

Zn

N a -

Zn

N a -

cr

NOj-

Zn 2+ Cu

I A) Zn(5) I Zn-^(afy) || Cu(.s-) | Cu^-'iag) B) Zn(5) i Zir^iaq) || Cu^'(aq) | Cu(5) C) Zn'^(r/g) | Zn{s) ]| Cu(i-) | Cu-(ot^) D) Zn^'-iaq) | Zn(i-) i| Cu^^Cofy) | Cu(5) E) Zn(5) I Cu(s) II Zn-^Ca^) | Cu^^Co^)

y 38. Consider the following standard electrode potentials:

Ag^(aq) + e ^

Mn~^iaq) + 2e-

AgCsO; = 0.80 V

Mn(5); £° = -1.18 V 0 4^ Which of the following statements is false concerning the electrochemical cell given below? Mn(.s-) I UiT\aq) || hg^iaq) \A) Under standard-state conditions, the cell potential is 1.98 V. B) The anode half-cell reaction is Mn(.s) —» Mn-^(c/fy) + 2e~. C) The cell potential decreases with time.

<li)) l l i e reducing agent is Ag(i).>;r::,:- f^/^y't ..'^n -E) The oxidizing agent is Ag'''(dq).

39. In a table of standard reduction potentials, the strongest oxidizing agents are the /^g/vcgo^ .species in the half-reactions with the ^xt E° values.

A) oxidized, most negative B) reduced, most negative C) oxidized, most positive

E) ' no<re of these

11

Pane I I

40. Which o f the_foJ!o^ving statements is true about a voltaic cell for vvhi

B) ' I he system is at equilibrium. C) It has D) The cathode is at a higher energy than the anode. E) The reaction is spontaneous. ]

41. Vvlrat is the copper(lI)-ion concentration at 25°C in the cell Zn{s) j Zn-"(1.0 M) || Cw~*{aq) I CuCvjif the measured cell potential is 1-01 V? The standard cell potential is

B) 0.000911 M J ^^^^j

C) 0.0302 M -y, o/ ^ / / o - . Czi D) 0.988 M E) LOOM

7..... -

42. WTrat is E of the following cell reaction at 25°C? £°ce i i = 0.460 V. Cu(.v) i Cu^XO.010 iU) 11 Ag^tO. 16 hf) \) A) 0.282 V . ,., a., B) 0.488 V •1?.*'

9 43. Cath5,dic#rot€eti<3B''fesults.,M

r'^C) iron is attached to a more active metaL B) iron is'anialgaiTiated^^ inQi'G'itryl C) iron is tin-plated for use as a t in can. D) iron is painted to protect it from corrosion. E) iron is made amphoteric.

44. Molten magnesium chloride is electrolyzed using inert electrodes and reactions represented by the following two half-reactions; 2 C l - ( 0 ^ C l 2 ( g ) + 2e-Mg2^(/) + 2e-->Mg(5) Concerning this electrolysis, which of the following statements is true? A) Oxidation occurs at the cathode. B) Mg-* ions are reduced at the anode. C) Electrons pass through the metallic part of the circuit from Mg-"*" ions to the OX' ion.

C^^y^S) Q\~ ions are reducing ageiTls?~^ b) 1 he anions in the electrolyte Ltndergo reduction.

Page 12

45. What is the half-reaction that occurs at the cathode during electrolysis of an aqueous potassium iodide solution? ~ ~ „

Reduction Half-Reaction

K-Haq) + e- K(.v) Mo^iaq) + 2e~ Mg(,y)

2H20(/) + 2e- H2C?) + 20H-(//ry)

IK'iaq) + 2e- H2(g)

h(s) + 2e- 2l-(aq)

02(g) + 4W{aq) + 4e- 2 H 2 O ( 0 A ) K^iaq) + e-^ K{s) B) K(5)-»K^ + e-C) l2(afy) + 2e- -> 2l-{aq)

, mJWll) V^02(g) + imaq) + 2e-( E) 2 H 2 5 ( ? ) y 2 e ' ^ 112(g)

E° (V) -2.93

-2.37

-0.83

0.00

0.54

123 J^^'^'f^

46. How many faradays are required to convert a mole of NO3' ions to NHa^ ions? A) 4 B) 5 C) 6 D j „ X ^ L

47. I f an electrolysis plant operates its electrolytic cells at a total current of 1.6 x 10^ A , how long wi l l it take to produce one metric-toa (one million grams) of Mg( i ) from seawater containingMg^^? (1 faraday = 96,485 coulombs) —

48r"*°A*q^n be prepared bv electronji^aptiire fron A ) «ct"^-B) ^"K. C) ^'Ar. D) ^

Page 13