The dissociation of phosgene is represented as follows:
` COCl_2 (g) hArr CO(g) +Cl_2( g) `
When a mixture of these three gasses at equilibrium is compressed at constant temperature , what happens to
the amount of CO in the mixture.

Explanation

To solve the problem, we need to analyze the dissociation of phosgene and how changes in pressure affect the equilibrium state of the reaction. Let's break it down step by step.

### Step-by-Step Solution:

1. **Write the Reaction**:
The dissociation of phosgene can be represented as:
\[
\text{COCl}_2 (g) \rightleftharpoons \text{CO}(g) + \text{Cl}_2(g)
...