Question

Chlorofluorocarbons photodissociate to produce chlorine atoms, cl•, which have been implicated in decreasing the concentration of ozone, o3, in the stratosphere. the decomposition of the ozone follows a reaction sequence of o3 cl• -> clo• o2 clo• o -> cl• o2 what role (factor affecting reaction rates) do chlorine atoms have in increasing the depletion rate of ozone

Answer 1

Answer:

The role that chlorine atoms have in increasing the depeltion rate ozone is that Cl acts as a catalyst.

Explanation:

• From the two steps of the reaction:

1. O₃ + Cl· → ClO· + O₂
2. ClO· + O → Cl· + O₂

• The overall reaction is: O₃ + O → 2O₂

• It is clear that ClO· is an intermediate that has been produced within the first step and has been consumed in the second step.

• Also, Cl· is considered as a catalyst in this reaction that it has been consumed in the first step and has been produced in the second step, which means that it does not get up in the reaction, that is the main characteristic of the catalyst.

• The catalyst usually increases the rate of the reaction by lowering its energy of activation (The minimum energy that is required to initiate the reaction) by proceeding the reaction in an alternative pathway (changing the reaction mechanism).

• Hence, the role affecting the reaction rate that chlorine atoms have in increasing the depletion rate of ozone that it acts as a catalyst and does not get used up in the reaction.