Reaction Rates and Equilibrium

If the forward reaction is endothermic, what can be deduced about the reverse reaction?

• It is also endothermic

• There is no energy change

• It is exothermic

Tags

NGSS.HS-PS1-4

When a reversible reaction is at equilibrium, which of these statements is true?

• The concentration of products is greater than the concentration of reactants

• The concentration of products remains constant over time

• The concentration of products is equal to the concentration of reactants

Tags

NGSS.HS-PS1-6

The equation for the Haber process is: N₂ + 3H₂ ⇌ 2NH₃. What gases will be present at equilibrium?

• Nitrogen and hydrogen

• Nitrogen, hydrogen and ammonia

• Ammonia only

One of the stages in sulfuric acid production is described by this equation: 2SO₂(g) + O₂(g) ⇌ 2SO₃(g). What will happen to the yield of SO₃ if the pressure is increased?

• It will go up

• It will go down

• It will stay the same

If the forward reaction in a reversible reaction is endothermic, what will be the effect of decreasing the temperature?

• It increases the amount of product present at equilibrium

• It decreases the amount of product present at equilibrium

• It does not affect the equilibrium

Tags

NGSS.HS-PS1-6

What effect on the equilibrium position is produced by adding a catalyst to a system in equilibrium?

• It decreases the yield of product

• It increases the yield of products

• It has no effect

Which of the two graphs reaches equilibrium?

• Neither

• The left

• Both

• The right

Which of the following is NOT true at equilibrium?

• The concentrations of reactants and products do not change.

• The forward and reverse reactions proceed at the same rate.

• The concentration of the reactants is equal to the concentration of the products.

• The forward and reverse reactions continue to occur.

Tags

NGSS.HS-PS1-6

Select all of the statements that are always correct about dynamic equilibrium

• established when the product and reactant concentrations are equal

• achieved when the forward and reverse reaction rates are same

• established when the concentration of reactants is unchanging

• achieved when the concentration ratio of reactants to products becomes stable

• achieved when the forward and reverse reactions stop occurring

Which statement describes this reaction at equilibrium?

• The concentration of N₂O₄(g) must equal the concentration of NO₂(g).

• The concentration of N₂O₄(g) and the concentration of NO₂(g) must be constant.

• The rate of the forward reaction is greater than the rate of the reverse reaction.

• The rate of the reverse reaction is greater than the rate of the forward reaction.