Question 1(multiple choice worth 3 points)

(07.07 mc)

a chemical equilibrium between gaseous reactants and products is shown.

n2(g) + 3h2(g) ⇌ 2nh3(g)

how will the reaction be affected if the pressure on the system is decreased?

it will shift toward the reactant side as there is lower pressure on the reactant side.
it will shift toward the product side as there is higher pressure on the product side.
it will shift toward the reactant side as there are a greater number of moles of gas on the reactant side.
it will shift toward the product side as there are a fewer number of moles of gas on the product side.
question 2 (true/false worth 2 points)

(07.07 lc)

according to le châtelier's principle, an increase in temperature will shift the equilibrium position toward the products in an endothermic reaction.

true
false
question 3 (matching worth 3 points)

(07.07 mc)

match the action to the effect on the equilibrium position for the reaction n2(g) + 3h2(g) ⇌ 2nh3(g).

match term definition
decreasing the pressure a) shift to the right
adding hydrogen gas b) shift to the left
adding a catalyst c) no effect
question 4(multiple choice worth 3 points)

(07.07 mc)

what change would shift the equilibrium system to the left?

a(g) + b(s) + energy ⇌ 3c(g)

adding more of gas c to the system
heating the system
increasing the volume
removing some of gas c from the system
question 5(multiple choice worth 3 points)

(07.07 mc)

what stress would shift the equilibrium position of the following system to the left?

n2o3(g) ⇌ no(g) + no2(g); δh is negative

decreasing the concentration of n2o3
heating the system
adding a catalyst
increasing the concentration of no
question 6(multiple choice worth 3 points)

(07.07 mc)

nitrogen dioxide gas is dark brown in color and remains in equilibrium with dinitrogen tetroxide gas, which is colorless.

2no2(g) ⇌ n2o4(g)

when a light brown colored mixture of the two gases at equilibrium was moved from room temperature to a higher temperature, the mixture turned dark brown in color. which of the following conclusions about this equilibrium mixture is true?

this reaction is exothermic because the system shifted to the left on heating.
this reaction is exothermic because the system shifted to the right on heating.
this reaction is endothermic because the system shifted to the left on heating.
this reaction is endothermic because the system shifted to the right on heating.
question 7(multiple choice worth 3 points)

(07.07 lc)

according to le châtelier's principle, how will a decrease in concentration of a reactant affect the equilibrium system?

shift it toward the products
shift it toward the reactants
shift it toward the side with higher total mole concentration
shift it toward the side with lower total mole concentration