Linda Thao
CHM1100C General Chemistry
Rasmussen College, Winter Qtr Term 2 - 2021
Instructor: Sabina Salkic
LeChatiler’s Principle
Chemical Equilibria Concept Test
Problem 1
Consider the reaction: A2 + B2 <---> 2AB The reactants are mixed together
and the following is a plot of the reactant and the product concentrations
with time: what is the value of the equilibrium
constant?
1. 1/2
2. 1
3. 2
4. 4
Problem 2
From a chemical handbook you find the equilibrium constants that give the
concentrations of Iodine vapor above water and oil: I2(water) <---> I2(g)
Kwater I2(oil) <---> I2(g) Koil But you want the equilibrium constant for the
partitioning of I2 between water and oil: I2(water) <---> I2(oil) K You can
obtain it as:
1. K = Kwater + Koil
2. K = KwaterKoil
3. K = Kwater/Koil
4. K = Koil/Kwater
Problem 3
Consider the reaction: N2 + 3H2 <---> 2NH3 The equilibrium constant at 400C
is K=0.5. Suppose we make a mixture with the following concentrations:
[ NH3] = 1.0M [ N2] = 1.0M [ H2] = 1.0M In which direction will the reaction
go?
, Linda Thao
CHM1100C General Chemistry
Rasmussen College, Winter Qtr Term 2 - 2021
Instructor: Sabina Salkic
1. N2 + 3H2 <---> 2NH3
2. 2NH3 --> N2 + 3H2
Problem 4
For the reaction: N2 + 3H2 <---> 2NH3 The relationship between Kc and Kp is:
1. Kp = Kc(RT)-2
2. Kp = Kc(RT)-1
3. Kp = Kc(RT)1
4. Kp = Kc(RT)2
Problem 5
Consider the equilibrium expression for the following reaction: CaCO3(s)<--->
CaO(s) + CO2(g) Which of the following is true?
1. The ratio of CaO(s) to CaCO3(s) will be the same in all samples of
this solid.
2. The vapor pressure of CO2(g) above a mixture of
CaCO3(s)/CaO(s) is independent of the relative amount of
these two solids.
Problem 6
The cobalt complexes participating in the equilibrium below comprise a
humidity sensor. From Le Chatelier's principle, when the air is moist, what
color is the cobalt complex? Co(H2O)6+2 + 4Cl- <---> CoCl4-2 + 6H2O
pink blue
1. Pink
2. Blue
3. White
4. Black
Problem 7
If the density of graphite is about 2 g/ml and that of buckyball is about 1.5
g/ml, in which direction would the application of high pressure drive the
equilibrium?
CHM1100C General Chemistry
Rasmussen College, Winter Qtr Term 2 - 2021
Instructor: Sabina Salkic
LeChatiler’s Principle
Chemical Equilibria Concept Test
Problem 1
Consider the reaction: A2 + B2 <---> 2AB The reactants are mixed together
and the following is a plot of the reactant and the product concentrations
with time: what is the value of the equilibrium
constant?
1. 1/2
2. 1
3. 2
4. 4
Problem 2
From a chemical handbook you find the equilibrium constants that give the
concentrations of Iodine vapor above water and oil: I2(water) <---> I2(g)
Kwater I2(oil) <---> I2(g) Koil But you want the equilibrium constant for the
partitioning of I2 between water and oil: I2(water) <---> I2(oil) K You can
obtain it as:
1. K = Kwater + Koil
2. K = KwaterKoil
3. K = Kwater/Koil
4. K = Koil/Kwater
Problem 3
Consider the reaction: N2 + 3H2 <---> 2NH3 The equilibrium constant at 400C
is K=0.5. Suppose we make a mixture with the following concentrations:
[ NH3] = 1.0M [ N2] = 1.0M [ H2] = 1.0M In which direction will the reaction
go?
, Linda Thao
CHM1100C General Chemistry
Rasmussen College, Winter Qtr Term 2 - 2021
Instructor: Sabina Salkic
1. N2 + 3H2 <---> 2NH3
2. 2NH3 --> N2 + 3H2
Problem 4
For the reaction: N2 + 3H2 <---> 2NH3 The relationship between Kc and Kp is:
1. Kp = Kc(RT)-2
2. Kp = Kc(RT)-1
3. Kp = Kc(RT)1
4. Kp = Kc(RT)2
Problem 5
Consider the equilibrium expression for the following reaction: CaCO3(s)<--->
CaO(s) + CO2(g) Which of the following is true?
1. The ratio of CaO(s) to CaCO3(s) will be the same in all samples of
this solid.
2. The vapor pressure of CO2(g) above a mixture of
CaCO3(s)/CaO(s) is independent of the relative amount of
these two solids.
Problem 6
The cobalt complexes participating in the equilibrium below comprise a
humidity sensor. From Le Chatelier's principle, when the air is moist, what
color is the cobalt complex? Co(H2O)6+2 + 4Cl- <---> CoCl4-2 + 6H2O
pink blue
1. Pink
2. Blue
3. White
4. Black
Problem 7
If the density of graphite is about 2 g/ml and that of buckyball is about 1.5
g/ml, in which direction would the application of high pressure drive the
equilibrium?
