Chemistry 2
Practice Final Exam
P4(s) + 5 O2(g) P4O10(s)
(a) K << 1
(b) K = 0
(c) K = 1
(d) K >> 1
(e) more information is needed.
(a) at equilibrium.
(b) to the right (product side) of the point of equilibrium.
(c) to the left (reactant side) of the point of equilibrium.
(d) can't tell from the available information.
(e) either b or c.
Reaction I: 2 NO2(g) 2 NO(g) + O2(g) Kc = 1.81 x 10-14
Reaction II: 2 NO(g) N2(g) + O2(g) Kc = 9.71 x 1017
Reaction III: 2 NO2(g) N2(g) + 2 O2(g) Kc = ?
(a) Kc = 1.86 x 10-32
(b) Kc = 5.69 x 10-5
(c) Kc = 7.18 x 102
(d) Kc = 1.76 x 104
(e) Kc = 5.36 x 1031
CO + 2 H2 CH3OH
(a) Kc = 0.09
(b) Kc = 0.90
(c) Kc = 1.00
(d) Kc = 1.11
(e) Kc = 11.1
CO2(g) + H2(g) CO(g) + H2O(g)
(1) increasing the concentration of H2
(2) decreasing the reaction temperature
(3) increasing the reaction pressure
(4) removing H2O from the system
(5) increasing the concentrations of H2 and CO2
(a) 1, 2, 3, 4, 5
(b) 1, 4, 5
(c) 1, 3, 4, 5
(d) 1, 2, 4, 5
(e) 3 only
2 SO2 + O2 2 SO3
Calculate the value of Kc at 700 °C for the reaction:
2 SO3 2 SO2 + O2
(a) Kc = 4.81 x 10-3
(b) Kc = 2.40 x 10-3
(c) Kc = 2.08 x 102
(d) Kc = 4.16 x 102
(e) Kc = 8.32 x 102
(a) NH3
(b) NH4Cl
(c) NaNO3
(d) Na2CO3
(e) Mg(NO3)2
(a) -0.1
(b) -1
(c) 0.1
(d) 1
(e) 2
(a) CH4 < H2O < NH3 < HCl
(b) HCl < H2O < NH3 < CH4
(c) HCl < NH3 < H2O < CH4
(d) CH4 < NH3 < H2O < HCl
(e) NH3 < CH4 < H2O < HCl
(a) Ka = 8
(b) Ka = 9 x 10-2
(c) Ka = 9 x 10-3
(d) Ka = 8 x 10-3
(e) Ka = 8 x 10-4
(a) pH = 2.9
(b) pH = 3.7
(c) pH = 5.1
(d) pH = 8.9
(e) pH = 9.3
Acid |
pKa |
Ka |
HCO2H |
3.75 |
1.8 x 10-4 |
H2S |
7.00 |
1.0 x 10-7 |
H2PO4- |
7.20 |
6.3 x 10-8 |
HCN |
9.22 |
6.0 x 10-10 |
NH4+ |
9.24 |
5.6 x 10-10 |
(a) 0.10 M H2S and 0.10 M NaHS
(b) 0.10 M NH4Cl and 0.10 M NH3
(c) 0.10 M HCN and 0.10 M NaCN
(d) 0.10 M HCO2H and 0.10 M NaHCO2
(e) 0.10 M NaH2PO4 and 0.10 M Na2HPO4
Pb(s) + SO42-(aq) PbSO4(s) + 2 e¯
(a) 8.34 hours
(b) 21.6 hours
(c) 43.1 hours
(d) 86.2 hours
(e) 194 hours
S2O32-(aq) + MnO4-(aq) SO42-(aq) + Mn2+(aq)
(a) 9
(b) 13
(c) 18
(d) 25
(e) 27
I. Cl2(g) is produced at the anode.
II. Na metal is produced at the cathode.
III. The reaction generates a current spontaneously.
(a) I & II
(b) I & III
(c) II & III
(d) I, II & III
(e) III only
2 Fe(s) + O2(g) + 2 H2O(l) 2 Fe2+(aq) + 4 OH-(aq)
(a) - 0.48 V
(b) - 0.04 V
(c) + 0.78 V
(d) + 0.84 V
(e) + 1.28 V
(a) Cu(s) can reduce Ni2+(aq) to Ni(s).
(b) H2(g) can reduce Ni2+(aq) to Ni(s).
(c) H2(g) can reduce Na+(aq) to Na(s).
(d) Hg(l) can reduce Au3+(aq) to Au(s).
(e) Hg(l) can reduce Sn4+(aq) to Sn2+(aq).
4 Fe(s) + 3 O2(aq) + 6 H2O(l) 2 Fe2O3 · 3 H2O(s)
(a) Fe is oxidized by the O2.
(b) Fe is oxidized by the H2O.
(c) O2 is oxidized by the Fe.
(d) O2 is reduced by the H2O.
(e) This is not an oxidation-reduction reaction.
I. 4 Al(s) + 3 O2(g) 2 Al2O3(s)
II. C6H12O6(s) + 6 O2(g) 6 CO2(g) + 6 H2O(g)
III. 8 H2S(g) + 4 O2(g) S8(s) + 8 H2O(l)
(a) I & II
(b) I & III
(c) II & III
(d) I, II, & III
(e) II only
P4O10(s) + 6 H2O(l) 4 H3PO4(aq)
Compound |
S°ac J/(K·mol) |
H2O(l) |
- 321 |
H3PO4(aq) |
- 1374 |
P4O10(s) |
- 2034 |
(a) - 3141 J/(K·mol)
(b) - 1536 J/(K·mol)
(c) - 981 J/(K·mol)
(d) + 981 J/(K·mol)
(e) + 2586 J/(K·mol)
(a) T = 0 K
(b) T = 25 °C
(c) P = 1 atm
(d) Concentration = 1 M
(e) T = 25 °C, P = 1 atm, Concentration = 1 M
Fe2O3(s) + 2 Al(s) Al2O3(s) + 2 Fe(s)
Compound |
H°ac kJ/mol |
S°ac J/(K·mol) |
Al(s) |
- 326 |
- 136 |
Al2O3(s) |
- 3076 |
- 761 |
Fe(s) |
- 416 |
- 153 |
Fe2O3(s) |
- 2404 |
- 757 |
(a) Entropy
(b) Enthalpy
(c) Le Châtelier principle
(d) Enthalpy and Entropy
(e) Enthaply, Entropy, and Le Châtelier principle
CH3OH(l) CH3OH(g)
H° = + 38 kJ/mol
S° = + 113 J/(K·mol)
(a) 0.34 K
(b) 3.0 K
(c) 150 K
(d) 340 K
(e) 3000 K
HF(aq) + H2O(l) H3O+(aq) + F-(aq)
(a) + 6.3 kJ/mol
(b) + 7.8 kJ/mol
(c) + 18 kJ/mol
(d) + 29 kJ/mol
(e) + 177 kJ/mol
2 NO(g) + 2 H2(g) N2(g) + 2 H2O(g)
Rate = k [NO]2 [H2]1
A possible mechanism for this reaction is given below. Assuming this mechanism is correct, which is the SLOW step ?
step 1: 2 NO(g) N2O2(g)
step 2: N2O2(g) + H2(g) N2O(g) + H2O(g)
step 3: N2O(g) + H2(g) N2(g) + H2O(g)
(a) step 1
(b) step 2
(c) step 3
(d) all of the above
(e) more information is needed.
2NO(g) + Cl2(g) 2 NOCl(g)
Initial [NO], M |
Initial [Cl2], M |
Initial Reaction Rate, M/s |
0.10 |
0.10 |
0.117 |
0.20 |
0.10 |
0.468 |
0.30 |
0.10 |
1.054 |
0.30 |
0.20 |
2.107 |
(a) Rate = k [NO]
1/2 [Cl2]
(a) k = 11.7 s-1
(b) k = 117 M-2 s-1
(c) k = 3.70 M
(a) k = 1.0 x 105 year-1
(b) k = 1.9 x 104 year-1
(c) k = 4.0 x 103 year-1
(d) k = 5.3 x 10-5 year-1
(e) k = 1.2 x 10-4 year-1
(a) 170 years old
(b) 1700 years old
(c) 3900 years old
(d) 8100 years old
(e) 17000 years old
(a) Ea = 25 kJ/molrxn
(b) Ea = 30 kJ/molrxn
(c) Ea = 95 kJ/molrxn
(d) Ea = 155 kJ/molrxn
(e) Ea = 215 kJ/molrxn
IMPORTANT CONSTANTS :
Gas constant |
R = 0.0821 L ·atm/(K·mol) |
|
R = 8.314 J/(K ·mol) |
Faraday's constant |
F = 96,500 C / 1 mol of e¯ |
|
1 C = 1 A ·sec |
Temperature |
K = °C + 273 |
Water ionization |
Kw = 1 x 10-14 |
STANDARD REDUCTION POTENTIALS E°red (V)
Na+(aq) + e¯ Na(s) |
- 2.71 V |
Mg2+(aq) + 2 e¯ Mg(s) |
- 2.37 V |
Zn2+(aq) + 2 e¯ Zn(s) |
- 0.76 V |
Fe2+(aq) + 2 e¯ Fe(s) |
- 0.44 V |
Ni2+(aq) + 2 e¯ Ni(s) |
- 0.25 V |
2 H+(aq) + 2 e¯ H2(g) |
0.00 V |
Sn4+(aq) + 2 e¯ Sn2+(aq) |
+ 0.13 V |
Cu2+(aq) + 2 e¯ Cu(s) |
+ 0.34 V |
O2(g) + 2 H2O(l) + 4 e¯ 4 OH-(aq) |
+ 0.40 V |
I2(s) + 2 e¯ 2 I-(aq) |
+ 0.54 V |
Hg2+(aq) + 2 e¯ Hg(l) |
+ 0.86 V |
Br2(l) + 2 e¯ 2 Br-(aq) |
+ 1.07 V |
Au3+(aq) + 3 e¯ Au(s) |
+ 1.50 V |