For the reaction, `CO(g) + H_(2)O(g) rarr CO_(2)(g) + H_(2)(g)` , at a given temperature, the equilibrium amount of `CO_(2)`(g) can be increased by:

Options

A. adding a suitable catalyst
B. adding an inert gas
C. decreasing the volume of the container
D. increasing the amount of CO(g)

Explanation

To determine how to increase the equilibrium amount of CO2 in the reaction:

\[ \text{CO(g)} + \text{H}_2\text{O(g)} \rightleftharpoons \text{CO}_2\text{(g)} + \text{H}_2\text{(g)} \]

we will analyze each option provided.

### Step 1: Understand the Reaction
The reaction involves the conversion of carbon monoxide (CO) and water vapor (H2O) into carbon dioxide (CO2) and hydrogen gas (H2). We need to find a way to shift the equilibrium position to favor the production of CO2.

### Step 2: Analyze Each Option

1. **Adding a Suitable Catalyst**
- A catalyst speeds up the rate of both the forward and reverse reactions equally but does not affect the position of equilibrium. Therefore, this option does not increase the amount of CO2 at equilibrium.
- **Conclusion:** This option is incorrect.

2. **Adding an Inert Gas**
- Adding an inert gas at constant volume does not change the partial pressures of the reacting gases. Since the equilibrium constant (Kp) depends on the partial pressures of the reactants and products, adding an inert gas does not affect the equilibrium concentrations.
- **Conclusion:** This option is incorrect.

3. **Decreasing the Volume of the Container**
- Decreasing the volume of the container increases the pressure of the system. According to Le Chatelier's principle, the system will shift towards the side with fewer moles of gas to counteract the change. In this case, the left side (reactants) has 2 moles of gas (1 CO + 1 H2O) and the right side (products) has 2 moles of gas (1 CO2 + 1 H2). Thus, changing the volume will not favor either side.
- **Conclusion:** This option is incorrect.

4. **Increasing the Amount of CO**
- According to Le Chatelier's principle, if we increase the concentration of a reactant (in this case, CO), the equilibrium will shift to the right to produce more products, including CO2. Therefore, this action will increase the amount of CO2 at equilibrium.
- **Conclusion:** This option is correct.

### Final Answer
The equilibrium amount of CO2 can be increased by **increasing the amount of CO**.

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