`20 ml` of` CO` is exploded with `30 ml` of` O_2 `at constant temperature and pressure. Final volume of the gases in ml will be

Options

A. 35
B. 40
C. 50
D. 60

Answer

To solve the problem of finding the final volume of gases after the explosion of 20 ml of CO with 30 ml of O2, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reaction**:
The reaction between carbon monoxide (CO) and oxygen (O2) produces carbon dioxide (CO2).
\[ 2 \text{CO} + \text{O}_2 \rightarrow 2 \text{CO}_2 \]

2. **Determine the Stoichiometry**:
From the balanced equation, we see that 2 volumes of CO react with 1 volume of O2 to produce 2 volumes of CO2. This means:
- 2 volumes of CO react with 1 volume of O2.
- 1 volume of CO reacts with 0.5 volumes of O2.

3. **Calculate the Limiting Reagent**:
We have:
- 20 ml of CO
- 30 ml of O2

According to the stoichiometry, 20 ml of CO would require:
\[ \text{Required O}_2 = \frac{20 \text{ ml CO}}{2} = 10 \text{ ml O}_2 \]
Since we have 30 ml of O2 available, CO is the limiting reagent.

4. **Calculate the Volume of CO2 Produced**:
Since CO is the limiting reagent, we can calculate how much CO2 is produced from the available CO:
- According to the reaction, 2 volumes of CO produce 2 volumes of CO2. Therefore, 20 ml of CO will produce:
\[ \text{Volume of CO}_2 = 20 \text{ ml CO} \rightarrow 20 \text{ ml CO}_2 \]

5. **Calculate the Final Volume of Gases**:
After the reaction, the remaining O2 can be calculated:
- Initial O2 = 30 ml
- O2 used = 10 ml (as calculated from the stoichiometry)
- Remaining O2 = 30 ml - 10 ml = 20 ml

Now, we add the volume of CO2 produced to the remaining volume of O2:
\[ \text{Final Volume} = \text{Volume of CO}_2 + \text{Remaining O}_2 = 20 \text{ ml CO}_2 + 20 \text{ ml O}_2 = 40 \text{ ml} \]

### Final Answer:
The final volume of the gases after the reaction is **40 ml**.

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