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DUE 3/10/
- Write the Kc and Kp expression for the reactions below.
2Cl 2 (g) + 2H 2 O(g) 4 HCl(g) + O 2 (g)
2
2
2
2
2
4
c
Cl H O
HCl O
K 2
H O
2
Cl
O
4
HCl
p
2 2
2
P P
P P
K
4 CuO(s) + CCl 4 (g) CO 2 (g) + 4 Cu(s) + 2 Cl 2 O(g)
4
2
2 2
c
CCl
CO Cl O
K
4
2 2
CCl
2
CO Cl O
p
P
P P
K
SO 3 (g) SO 2 (g) + ½ O 2 (g)
3
2
1
2 2
c
SO
SO O
K
3
2 2
SO
2
1
SO O
p
P
P P
K
P 4 (s) + 10 Cl 2 (g) 4 PCl 5 (s)
10
2
c
Cl
K
10
Cl
p
2
P
K
CCl 4 (l) C(s) + 2 Cl 2 (g)
2
c 2
K Cl
2
p Cl 2
K P
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- For which of the following reactions does Kp = Kc There may be more than one?
NH 3 (g) + 3O 2 (g) 2N 2 (g) + 6H 2 O(l)
3 H 2 (g) + N 2 (g) 2NH 3 (g)
CO(g) + Cl 2 (g) COCl(g) +Cl(g)
H 2 (g) + I 2 (g) 2 HI(g)
2 SO 2 (g) + O 2 (g) 2 SO 3 (g)
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3 Consider the following equilibrium?
NH 4 CO 2 NH 2 (s) 2 NH 3 (g) + CO 2 (g) Kp = 2.5 10
at 310 K
What are the equilibrium pressures of NH 3 and CO 2 at 310 K?
NH 4 CO 2 NH 2 (s)
2 NH 3 (g) + CO 2 (g)
initial - 0 0
change - 2x x
equil - 2x x
(^334)
CO
2
p NH
K P P 2 x x 4 x 2. 5 10
3 2
2 3
4
x
P x 3. 97 10 atm
2
CO 2
P 2 x 7. 94 10 atm
2
NH 3
DUE 3/10/
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- Consider the exothermic reaction 4 NO 2 (g) + O 2 (g) 2 N 2 O 5 (g).
Indicate the effect of the following stresses on the equilibrium.
(shift to products, shift to reactants, no effect)
a) a decrease in the pressure of NO 2 (shifts to reactants)
b) an increase in the pressure of N 2 O 5 (shifts to reactants)
c) a decrease in temperature. (shift to products)
d) addition of a catalyst (no effect)
e) an increase in the volume of the container holding the gases. (shifts to reactants)
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- Consider the reaction 4 CuO(s) + CCl 4 (g) CO 2 (g) + 4 Cu(s) + 2 Cl 2 O(g). Kp at 400
°C is 625 for this reaction. Write the algebraic equation needed to solve for the equilibrium
pressures of CCl 4 (g), CO 2 (g), and Cl 2 O(g) at 400 °C. Assume initially that the concentrations
are 1.0 atm for CCl 4 (g) , 2.0 atm for CO 2 (g) and 3.0 atm for Cl 2 O(g).
4 CuO(s) + CCl 4 (g)
CO 2 (g) + 4 Cu(s) + 2 Cl 2 O(g)
initial - 1.0 2.0 - 3.
change - x x - 2x
equil - 1.0 - x 2.0 - x - 3.0 - 2x
1. 0 x
3. 0 2 x 2. 0 x
P
P P
K
2
CCl
CO
2
Cl O
p
4
2 2
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- For the reaction 2 SO 2 (g) + O 2 (g) 2 SO 3 (g), Kc = 0.200 at 100 °C.
If 1.0 moles of SO 2 is mixed with 0.50 moles of SO 3 and 0.50 moles of O 2 in a 5.0 L
chamber, will there be more or less than 1.0 mole of SO 2 when equilibrium is reached. (Hint:
use the reaction quotient to determine the answer)
0. 10 M
5 L
- 50 mol
SO 3
0. 20 M
5 L
- 0 mol
SO 2
0. 10 M
5 L
- 50 mol
O 2
5
2 0. 1
1
SO O
SO
Q 2
2
2
2
2
2
3
since Q > K there are too many products and thus will be more SO 2 (s) at equilibrium
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- Find the concentration of Mg
2+ ions in a saturated solution of MgF 2 (Ksp = 6.6x
__________________________________________________________________________
MgF 2 (s)
Pb
2+
+ 2F
i 0 0
c x 2x
e x 2x
2 3 2 2
sp K Mg F x( 2 x) 4 x
3
3
1 9 3
1
sp
- 2 10
4
- 6 10
4
K
x
[Mg
2+
] = x = 1.2 10
