Decomposition of NH3 and Zero-Order Reactions : A Closer Look

The video tutorial explains the concept of zero order reactions, using the decomposition of ammonia as an example. It describes how the rate of reaction is independent of the concentration of ammonia, as the reaction rate is determined by the number of ammonia molecules bound to a platinum surface. Two cases are considered: one with low ammonia concentration and another with increased concentration. Despite the increase, the reaction rate remains unchanged, illustrating the principle that zero order reactions are unaffected by reactant concentration.

What is the relationship between the rate of a zero order reaction and the concentration of reactants?

• The rate is directly proportional to the concentration.

• The rate is inversely proportional to the concentration.

• The rate is independent of the concentration.

• The rate decreases as concentration increases.

In the decomposition of ammonia on a platinum surface, what happens to the reaction rate when the concentration of ammonia is increased?

• The reaction rate remains the same.

• The reaction rate decreases.

• The reaction rate increases.

• The reaction rate becomes zero.

What is the role of the platinum surface in the decomposition of ammonia?

• It increases the concentration of ammonia.

• It provides a surface for ammonia molecules to bind.

• It changes the order of the reaction.

• It acts as a reactant.

Why does the increase in ammonia concentration not affect the rate of a zero order reaction?

• Because the reaction depends on the number of molecules bound to the surface.

• Because the reaction is limited by pressure.

• Because the reaction is already at maximum rate.

• Because the reaction is limited by temperature.

What determines the rate of a zero order reaction like ammonia decomposition?

• The number of ammonia molecules bound to the platinum surface.

• The total concentration of ammonia in the system.

• The temperature of the reaction.

• The pressure of the system.