When a jar containing gaseous mixture of equal volumes of `CO_(2)` and `H_(2)` is placed in a solution of sodium hydroxide, the solution level will

Options

A. Rise
B. Fall
C. Remain constant
D. Become zero

Answer

To solve the problem of what happens to the solution level when a jar containing a gaseous mixture of equal volumes of CO₂ and H₂ is placed in a solution of sodium hydroxide (NaOH), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Gaseous Mixture**:
- The jar contains equal volumes of carbon dioxide (CO₂) and hydrogen (H₂).
- The total volume of gas in the jar is the sum of the volumes of CO₂ and H₂.

2. **Introducing Sodium Hydroxide (NaOH)**:
- When the jar is placed in a solution of sodium hydroxide, the NaOH solution is capable of reacting with CO₂.
- H₂ does not react with NaOH under normal conditions.

3. **Reaction of CO₂ with NaOH**:
- CO₂ reacts with NaOH to form sodium carbonate (Na₂CO₃) or sodium bicarbonate (NaHCO₃) depending on the concentration and conditions.
- The reaction can be represented as:
- CO₂ + NaOH → NaHCO₃ (sodium bicarbonate)
- Further, NaHCO₃ can react with more NaOH to form Na₂CO₃ (sodium carbonate).

4. **Absorption of CO₂**:
- As CO₂ is absorbed by the NaOH solution, it decreases the amount of gas present in the jar.
- Since H₂ does not react, its volume remains unchanged.

5. **Change in Solution Level**:
- The absorption of CO₂ leads to the formation of new compounds (NaHCO₃ or Na₂CO₃) in the solution.
- This process effectively removes CO₂ from the gaseous phase, which results in a decrease in pressure above the liquid.
- Consequently, the liquid level in the jar will rise because the gas volume decreases, allowing more liquid to occupy the space.

6. **Conclusion**:
- The solution level will increase due to the absorption of CO₂ by the NaOH solution and the subsequent formation of new compounds.

### Final Answer:
The solution level will **increase** when the jar containing the gaseous mixture of CO₂ and H₂ is placed in a solution of sodium hydroxide.