2) Of the following questions, which ones are thermodynamic, rather than kinetic concepts?

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1 AP Chemisry Tes (Chaper 12) Muliple Choice (40%) 1) Which of he following is a kineic quaniy? A) Enhalpy B) Inernal Energy C) Gibb s free energy D) Enropy E) Rae of reacion 2) Of he following quesions, which ones are hermodynamic, raher han kineic conceps? I) Can subsances reac when we pu hem ogeher? II) If a reacion happens, how fas will i occur? III) Wha is he mechanism by which he reacion occurs? IV) If subsances reac, wha energy changes occur? A) I and III B) II and IV C) I and IV D) II and III E) I, III and IV 3) One of he reacions ha is used o produce gaseous hydrogen commercially follows. A proper expression for he rae of his reacion could be?. H 2 O (g) + CO (g) H 2 (g) + CO 2 (g) A) [CO 2 ] B) - [H 2 ] C) k D) [CO] E) [H 2 O] 4) Which of he following reacions would be expeced o be he slowes? A) H + (aq) + CN - (aq) HCN (aq) B) 3 H + (aq) + PO 3-4 (aq) H 3 PO 4 (aq) C) Pb 2+ (aq) + SO 2-4 (aq) PbSO 4 (s) D) O (g) + O (g) O 2 (g) E) O 2 (g) + O (g) O 3 (g) 5) Wha can be said abou he soichiomeric coefficiens of a balanced chemical equaion for a reacion and he powers o which he concenraions are raised in he rae law expression? A) There is an exac relaionship beween he wo. B) The powers can be equal o he number of molecules ha are formed. C) The powers are equal o he number of molecules wih effecive collisions in he fases sep of he reacion mechanism. D) No much can be said excep ha here is no necessary relaionship. E) The powers equal he coefficiens of he equaion. 6) Please consider he following gas phase reacion and is experimenally observed rae law. Wha is he overall order of he reacion? rae = k[a] 2 [B] A) 1 s B) 2 nd C) 3 rd D) 0 order

2 7) Please consider he following gas phase reacion and is experimenally observed rae law. Which one would affec he value of he specific rae consan, k? rae = k[a] 2 [B] A) Decreasing he emperaure B) Changing he concenraion of A C) Changing he concenraion of B D) Changing he concenraion of C E) Leing he reacion proceed for a long ime 8) The unis of he rae consan for a second order reacion could be?. A) M -1 s -1 B) M -2 s -1 C) M s -1 D) s -1 E) M 2 s -1 9) Please consider he following hypoheical reacion found o be firs order in X and second order in Y. Wha are he unis of he rae k, he specific rae consan, if he reacion rae is expressed in unis of M/s? X + 2 Y Producs A) M s -1 B) M -2 s -1 C) M -3 s -1 D) M 2 s -1 E) M -1 s -1 10) Please consider he following hypoheical reacion and is experimenally deermined specific rae consan, k. Wha overall order is his reacion? X + Y Producs k = s -1 A) 0 order B) 1 s order C) 2 nd order D) 3 rd order E) Canno be deermined 11) Please consider he following hypoheical reacion and is experimenally deermined specific rae consan, k. Which rae law expression could be correc? X + Y Producs k = M -3 min -1 A) rae = k[x] 3 B) rae = k[x] 2 [Y] C) rae = k[x][y] D) rae = k E) rae = k[x] 3 [Y] 12) Please consider he following gas phase reacion and is experimenally deermined rae law expression. If he concenraion of A is ripled and he concenraion of B is doubled, he reacion rae would be increased by a facor of?. rae = k[a] 2 [B] A) 6 B) 9 C) 12 D) 18 E) 36

3 13) Which of he following saemens is false? A) In order for a reacion o occur, reacan molecules mus collide wih each oher. B) According o he collision heory, a hree-body collision is less likely han a wobody collision. C) In reacions ha are second order in one reacan and firs order in anoher, he slow sep generally involves a hree-body collision of hese reacans. D) The ransiion sae is a shor-lived, high energy sae, inermediae beween reacans and producs. 14) Which one is he rae law expression for his elemenary, gas phase reacion? NO 3 + CO NO 2 + CO 2 A) rae = k[no 3 ] 2 B) rae = k[co] C) rae = k[no 3 ] 2 [CO] 2 D) rae = k[no 2 ][CO 2 ] E) rae = k[no 3 ][CO] 15) We are sudying he following reacion. We make a plo of ln[a] vs. ime as he reacion proceeds. This plo urns ou o be linear wih a slope of Wha is he rae law expression for his reacion? 2 A 3 B A) rae = 0.25 s -1 [A] B) rae = 0.25 M -1 s -1 ln[a] C) rae = 0.25 M -1 s -1 [A] 2 D) rae = s -1 [A] E) rae = M -1 s -1 [A] 2 16) Which graph illusraes a 2 nd order reacion, A B A) B) [A] 1/[A] C) D) ln [A] 1/[A]

4 Please use he following informaion o answer quesions Sep 1: Sep 2: Sep 3: C + D E + 2 M D + E + B J 17) Please wrie he overall, balanced reacion. 18) Please idenify all inermediaes. 19) Please idenify he producs. 20) Please idenify he reacans. Problems (60%) Please show all your work for any credi!!! 1) Please wrie he rae law expression for his reacion, based on he following experimenal daa. NO + O 2 + N 2 Producs Experimen Iniial [NO] (M) Iniial [O 2 ] (M) Iniial [N 2 ] (M) Iniial Rae of Disappearance of NO (M/min) X X X X 10-2 Please use he following experimenal daa o answer quesions 2-3. A + B + C Producs Experimen Iniial [A] (M) Iniial [B] (M) Iniial [C] (M) Iniial Rae of Reacion (M/s) ) Please wrie he rae law expression for his reacion. 3) Wha would be he iniial rae of reacion if he iniial concenraion of A was 0.40 M, he iniial concenraion of B was 0.20 M and he iniial concenraion of C was 0.10 M?

5 4) Please wrie he rae law expression, using he following experimenal daa. CO 2 (g) C (s) + O 2 (g) Time (s) [CO 2 ] (M) ) Wha is he half-life of his reacion? 2 A A 2 k = 2.34 s -1 6) Please consider his reacion: 2 NO 2 (g) 2 NO (g) + O 2 (g) rae = M -1 s -1 [NO 2 ] mol NO 2 is placed ino a 6.00-L flask. Wha mass of O 2 is presen afer 1.80 s? 7) Please consider his reacion: 2 NH 3 (g) N 2 (g) + 3 H 2 (g) k = 1.21 M s mol NH 3 is placed ino a 3.00-L flask. How long will he reacion proceed o consume 80.0% of he original NH 3? 8) Please wrie he rae law for his reacion mechanism. Sep 1: H 2 2 H (Fas, equilibrium) Sep 2: H + CO HCO (Slow) Sep 3: H + HCO H 2 CO (Fas) Formulas: 1/2 = [A] 0 1/2 = /2 = 1 2k k k[a] 0

6 AP Chemisry Tes (Chaper 12) Name Muliple Choice (40%) 1) 11) 2) 12) 3) 13) 4) 14) 5) 15) 6) 16) 7) 17) 8) 18) 9) 19) 10) 20) Problems (70%) Please show all your work for any credi. 1) Please use only he fron side of each piece of paper. 2) Please number your problems clearly and consecuively. 3) Please saple your problems o he back of his page in numerical order. 4) Please wrie on he paper in he convenional manner. 5) Please do no make a separae lis of answers. Record your answer a he end of he work supporing your answer. 6) Please circle/box your answer o any problems.

7 AP Chemisry Tes (Chaper 12) Name Key Muliple Choice (40%) 1) E 11) E 2) C 12) D 3) B 13) D 4) B 14) E 5) D 15) A 6) C 16) B 7) A 17) A + 2 B + 2 D 2 M + J 8) A 18) C E 9) B 19) M J 10) B 20) A B D Problems (60%) 1) rae = 2.13 M -3 min -1 [NO] 2 [O 2 ][N 2 ] 2) rae = 0.89 M -2 s -1 [B][C] 2 3) M/s 4) rae = M -1 s -1 [CO 2 ] 2 5) 1 s order!! s 6) 2 nd order!! 7.04 g 7) 0 h order!! 1.16 s 8) rae = k [H 2 ] 1/2 [CO]