Download Exam 2A Cover Sheet - General Chemistry II | CHEM 113 and more Exams Chemistry in PDF only on Docsity!
EXAM 2A COVER SHEET – PLEASE FILL IN
THE INFORMATION BELOW AND HAND IT IN
WITH YOUR SCANTRON. YOU WILL STILL
NEED TO SHOW ID WHEN YOU HAND YOUR
SCANTRON.
HONOR PLEDGE : I HAVE NOT GIVEN,
RECEIVED, OR USED ANY UNAUTHORIZED
ASSISTANCE.
Name:________________________________
Signature:______________________________
Student number:_________________________
For this exam you will need a pencil, a TI-30Xa calculator and your student ID. No other materials are allowed at your desk during the exam. Calculators may not be shared. Be sure to include your name, student ID (not your SSN) and version letter on your answer sheet. You will only be scored on your scantron answers, so be careful. There are 25 questions, equally weighted at 4 points each. When you have finished taking the exam, the answer sheet and cover sheet must be turned in. Take a couple of deep breaths, relax and just do your best! Potentially useful equations: T(in K) = T(in°C) + 273. € ln
K 2
K 1
= €
Δ Hrxn R
T 2
T 1
) (R = 8.314 J/mol•K) M = n/V Kp = Kc(RT)Δn^ (R = 0.0821 L•atm/mol•K) PV = nRT (R =0.0821 L•atm/mol•K) Quadratic Equation: ax^2 + bx + c = 0 Quadratic Equation Solution: x = € − b ± b 2 − 4 ac 2 a pH = – log[H 3 O+] pKa = – logKa Kw = 1.0 x 10–^14 (at 25oC) Kw = [H 3 O+][OH–] 1A 8A 1 H 1.008 2A 3A 4A 5A 6A 7A 2 He
3 Li
4 Be
5 B
6 C
7 N
8 O
9 F
10 Ne
11 Na
12 Mg 24.31 3B 4B 5B 6B 7B 8B 8B 8B 1B 2B 13 Al
14 Si
15 P
16 S
17 Cl
18 Ar
19 K
20 Ca
21 Sc
22 Ti
23 V
24 Cr
25 Mn
26 Fe
27 Co
28 Ni
29 Cu
30 Zn
31 Ga
32 Ge
33 As
34 Se
35 Br
36 Kr
37 Rb
38 Sr
39 Y
40 Zr
41 Nb
42 Mo
43 Tc (98) 44 Ru
45 Rh
46 Pd
47 Ag
48 Cd
49 In
50 Sn
51 Sb
52 Te
53 I
54 Xe
55 Cs
56 Ba
57 La
72 Hf
73 Ta
74 W
75 Re
76 Os
77 Ir
78 Pt
79 Au
80 Hg
81 Tl
82 Pb
83 Bi
84 Po (209) 85 At (210) 86 Rn (222) 87 Fr (223) 88 Ra
89 Ac
104 Rf
105 Ha
106 Sg
107 Bh
108 Hs (265) 109 Mt (266)
- A container contains 6.25 g CaCO 3 (s), 1.76 g CaO(s) and 0.035 atm of CO 2 (g) at 900 °C. Is the system at equilibrium, and if not, how would it reach equilibrium? CaCO 3 (s) CaO(s) + CO 2 (g) for which KP = 1.04 at 900°C a) Yes, this system is at equilibrium. b) No, the system would shift to form more products. c) No, the system would shift to form more reactants. d) There is no way to answer this question based upon the information provided.
- KC will be equal to KP if: a) The number of moles of gaseous products is greater than the number of moles of gaseous reactants. b) The number of moles of products equals the number of moles of reactants. c) All the reactants and products are gases. d) The number of moles of gaseous products is equal to the number of moles of gaseous reactants.
- An empty 2.00 L flask at 250.°C was filled with PCl 5 (g) to a pressure of 0.249 atm, and then the PCl 5 was allowed to decompose as shown below. At equilibrium, the total pressure inside the flask was observed to be 0.471 atm. What is the pressure of PCl 5 at equilibrium? PCl 5 (g) Cl 2 (g) + PCl 3 (g) a) 0.027 atm b) 0.222 atm c) 0.465 atm d) 0.471 atm
Use the information shown here to solve problems 8, 9 and 10. CO(g) + H 2 O(g) H 2 (g) + CO 2 (g) KC =0.6944 at 1200. K ΔHrxn = - 41.2 kJ/mol
- For the reaction listed above, 4.0 mol each of CO, H 2 O, H 2 and CO 2 (i.e. 4.0 mol of each component of the system) are mixed in a 2.0 L flask. What will happen? a) Nothing – the system is at equilibrium. b) There will be a shift towards forming more products. c) There will be a shift towards forming more reactants. d) Cannot be determined from the information provided.
- Starting with the initial concentrations provided in the question above, what will be the equilibrium concentration of CO 2? a) 1.6 M b) 1.8 M c) 2. 0 M d) 2. 2 M
- What is KC for this process at 200.K? a) 7.49 × 10
- 10 b) 14. c) 6.44 × 108 d) 1.34 × 10 9
- What is the pH of a solution made by dissolving 15 g of NaOH in enough water to make 7 50 mL of solution? a) 13. b) 12. c) 0. d) - 0.
- Fill in the blank for the following proton-transfer process shown below. H 2 PO 4 - (aq) + CH 3 NH 2 (aq) HPO 42 - (aq) + __________ a) CH 3 NH 3
- (aq) c) CH 4 NH 2 +(aq) d) H 3 O+(aq)
- Below you will find two steps that can be manipulated to give you the overall equation for the reaction of methane, steam and oxygen to form carbon dioxide and hydrogen. What is the balanced overall reaction? What is KP for this overall reaction? This is from problem 17.99 in the homework. 2CH 4 (g) + O 2 (g) 2CO(g) + 4H 2 (g) KP = 9.34 × 10 28 at 1000.K CO(g) + H 2 O(g) CO 2 (g) + H 2 (g) KP = 1.374 at 1000.K a) 2CH 4 (g) + O 2 (g) + 2H 2 O(g) 2CO 2 (g) + 6H 2 (g), KP = 1.76 × 10 29 b) 2CO 2 (g) + 6H 2 (g) 2CH 4 (g) + O 2 (g) + 2H 2 O(g), KP = 5.67 × 10 -^30 c) CH 4 (g) + 2 O 2 (g) CO 2 (g) + 2H 2 O(g), KP = 1. 28 × 1029 d) 2CH 4 (g) + O 2 (g) + CO(g) + H 2 O(g) CO 2 (g) + 5H 2 (g), KP = 9.34 × 10 28
- The decomposition of NO 2 (shown below) has a KP = 4.8 × 10
- 6 at a certain temperature. If 1.36 atm of NO 2 is placed in a flask at this temperature, then what is the equilibrium pressure of NO? 2NO 2 (g) 2NO(g) + O 2 (g) a) 0.0022 atm b) 0.015 atm c) 0.026 atm d) 1.4 atm
- For the process below, if 1.0 mol of O 2 and 0. 80 mol of N 2 are placed in a 2.0 L flask at 2000 °C, then what is the equilibrium concentration of NO? O 2 (g) + N 2 (g) 2NO(g) KC = 4.8 × 10
- 4 at 2000°C a) 2.4 × 10 -^4 b) 2.5 × 10
- 3 c) 4.9 × 10
- 3 d) 9.8 × 10 -^3
- In class we saw a demonstration of the following equilibrium process. What was the result of the addition of HCl(aq) solution to the initial purple (containing Co(H 2 O) 6 2+^ and CoCl 4 2 - ) solution? Co(H 2 O) 6 2+ (aq) + 4Cl - (aq) CoCl 4 2 - (aq) + 6 H 2 O(l) Pink blue a) The solution turned pink. b) The solution turned blue. c) There was no change to the solution. d) The solution became colorless.
