Equilibrium Reactions and Rates

The video tutorial discusses reversible reactions and dynamic equilibrium, emphasizing that while the rates of forward and reverse reactions are equal at equilibrium, the amounts of reactants and products are not necessarily equal. It explains how initial conditions affect reaction direction and how adding products like NH3 can shift equilibrium. The tutorial also includes a graphical representation of a reaction reaching equilibrium, illustrating changes in reactant and product amounts over time.

What is true about the rates of forward and reverse reactions at equilibrium?

• The forward rate is always higher.

• They are equal.

• The reverse rate is always higher.

• They are both zero.

In a dynamic equilibrium, what happens to the amounts of reactants and products?

• They increase indefinitely.

• They remain constant.

• They become zero.

• They fluctuate constantly.

In the context of equilibrium, what does it mean for a reaction to be dynamic?

• The reaction only proceeds in one direction.

• The reaction rates change constantly.

• The reaction stops completely.

• The reaction continues at a constant rate.

If a reaction starts with only reactants, in which direction will it initially proceed?

• It will not proceed.

• In the forward direction.

• In the reverse direction.

• Both directions equally.

What happens to the rate of the reverse reaction when extra product is added to a system at equilibrium?

• It stops completely.

• It increases.

• It decreases.

• It remains the same.

What is the effect of adding NH3 to a system at equilibrium?

• The reverse reaction rate increases.

• The reverse reaction rate decreases.

• The forward reaction rate increases.

• The system remains at equilibrium.

In the example reaction, what is the initial amount of substance A?

• 0.2 moles

• 0.3 moles

• 0.4 moles

• 0.5 moles

How does the amount of substance B change at equilibrium in the example reaction?

• It increases by 0.15 moles.

• It remains the same.

• It decreases by 0.3 moles.

• It increases by 0.3 moles.

What is the mole ratio of A to C in the example reaction?

• 1:1

• 2:1

• 3:1

• 1:2

What is the final amount of substance C at equilibrium in the example reaction?

• 0.25 moles

• 0.15 moles

• 0.35 moles

• 0.45 moles