Name:______Date:______
Ch 13/14 Review
1) What is the volume of 15 grams of H2 gas at 780 mm Hg and 37°C?
2) A sample of gas occupies 2.52 L at 1.00 atm. What is the new volume if the pressure is increased to 1.35 atm?
3) Magnesium reacts with hydrochloric acid according to the following reaction:
Mg(s) + 2HCl(aq) à MgCl2(aq) + H2(g)
How many grams of magnesium are required to produce 790 mmHg of pressure at 25°C in a 750mL container?
4) Gloria makes a mixture of gases: 50 grams of Ne, 15 grams of H2 and 25 grams of He.
a. What is the mole fraction of each gas?
b. If the mixture occupies 500 mL at 300K, what is the total pressure?
c. What is the partial pressure of each gas?
5) A sample of gas is collected over water in a eudiometer at 295 K. How many moles of gas were collected if the volume of gas is 34.1 mL and the pressure is 1.05 atm.
6) Write the K expression for each of the following reactions:
a. 4A(s) + 3B2(g) ó 2A2B3(g)
b. X+(aq) + Y-(aq) ó XY(s)
c. CD2(s) ó C+(aq) + 2D-(aq)
7) Calculate K for the following reactions:
a. At equilibrium, [H2] = 0.0018 M, [I2] = 0.0031 M, and [HI] = 0.0177 M.
H2(g) + I2(g) ó 2HI(g)
b. At equilibrium, [BC] = 0.9 M, [AC] = 2.3 x 10-2 M, and [B2] = 3.0 x 10-3 M.
2A(s) + 2BC(aq) ó 2AC(aq) + B2(g)
8) Determine the equilibrium concentrations of all species for the following reactions:
a. The starting concentration of AB is 0.40 M.
2AB(g) + C2D(s) ó A2D(g) + 2CB(s) K = 1.12 x 10-5
b. The starting concentration of NOCl is 0.10 M.
2NO(g) + Cl2(g) ó 2NOCl(g) K = 1.11 x 103
9) Consider an aqueous solution containing oxalic acid ([H2C2O4] = 0.38 M), fluoride ions ([F-] = 4.13 M), hydrofluoric acid ([HF] = 1.75 M) and oxalate ions ([C2O42-] = 0.14 M):
H2C2O4(aq) + 2F-(aq) ó 2HF(aq) + C2O42-(aq) K = 2.1
Is this system at equilibrium? If not, in which direction will it shift?
10) For the following exothermic reaction at equilibrium, predict which way the reaction will shift to counteract the following changes:
4NH3(g) + 5O2(g) ó 4NO(g) + 6H2O(g)
a. the system is heated
b. the volume of the container is decreased
c. remove H2O(g)
d. add NO(g)
e. add O2(g)
f. add a catalyst
Name:______Date:______
Ch 13/14 Review
1) What is the volume of 15 grams of H2 gas at 780 mm Hg and 37°C?
V = 184 L
2) A sample of gas occupies 2.52 L at 1.00 atm. What is the new volume if the pressure is increased to 1.35 atm?
V = 1.87 L
3) Magnesium reacts with hydrochloric acid according to the following reaction:
Mg(s) + 2HCl(aq) à MgCl2(aq) + H2(g)
How many grams of magnesium are required to produce 790 mmHg of pressure at 25°C in a 750mL container?
n = 0.032 moles H2(g) 0.78 g Mg
4) Gloria makes a mixture of gases: 50 grams of Ne, 15 grams of H2 and 25 grams of He.
- What is the mole fraction of each gas?
nT = 16.18 moles XH2 = 0.46 XNe = 0.15
XHe = 0.39
- If the mixture occupies 500 mL at 300K, what is the total pressure?
P = 800 atm
- What is the partial pressure of each gas?
PNe = 120 atm PH2 = 368 atm PHe = 312 atm
5) A sample of gas is collected over water in a eudiometer at 295 K. How many moles of gas were collected if the volume of gas is 34.1 mL and the pressure is 1.05 atm.
0.0014 moles of gas
6) Write the K expression for each of the following reactions:
a. 4A(s) + 3B2(g) ó 2A2B3(g)
[A2B3]2/[B2]2
b. X+(aq) + Y-(aq) ó XY(s)
1/[X+][Y-]
c. CD2(s) ó C+(aq) + 2D-(aq)
[C+][D-]2
7) Calculate K for the following reactions:
- At equilibrium, [H2] = 0.0018 M, [I2] = 0.0031 M, and [HI] = 0.0177 M.
H2(g) + I2(g) ó 2HI(g)
K = 56.1
- At equilibrium, [BC] = 0.9 M, [AC] = 2.3 x 10-2 M, and [B2] = 3.0 x 10-3 M.
2A(s) + 2BC(aq) ó 2AC(aq) + B2(g)
K = 1.96 x 10-6
8) Determine the equilibrium concentrations of all species for the following reactions:
a. The starting concentration of AB is 0.40 M.
2AB(g) + C2D(s) ó A2D(g) + 2CB(s) K = 1.12 x 10-5
[A2D] = 4.5 x 10-6 M [AB] = 0.4 M
- The starting concentration of NOCl is 0.10 M.
2NO(g) + Cl2(g) ó 2NOCl(g) K = 1.11 x 103
[Cl2] = 0.013 M [NOCl] = 0.086 M [NO] = 0.026 M
9) Consider an aqueous solution containing oxalic acid ([H2C2O4] = 0.38 M), fluoride ions ([F-] = 4.13 M), hydrofluoric acid ([HF] = 1.75 M) and oxalate ions ([C2O42-] = 0.14 M):
H2C2O4(aq) + 2F-(aq) ó 2HF(aq) + C2O42-(aq) K = 2.1
Is this system at equilibrium? If not, in which direction will it shift?
Q = 0.066 Q<K, RIGHT
10) For the following exothermic reaction at equilibrium, predict which way the reaction will shift to counteract the following changes:
4NH3(g) + 5O2(g) ó 4NO(g) + 6H2O(g)
g. the system is heated LEFT
h. the volume of the container is decreased LEFT
i. remove H2O(g) RIGHT
j. add NO(g) LEFT
k. add O2(g) RIGHT
l. add a catalyst NO CHANGE