If ten volumes of dihydrogen gas reacts with five volumes of dioxygen gas, how many volumes of water vapour would be produced?

Explanation

To solve the problem of how many volumes of water vapor would be produced when ten volumes of dihydrogen gas react with five volumes of dioxygen gas, we can follow these steps:

### Step-by-Step Solution:

1. **Write the Balanced Chemical Equation:**
The balanced equation for the reaction between dihydrogen (H₂) and dioxygen (O₂) to form water (H₂O) is:
\[ 2H_2 + O_2 \rightarrow 2H_2O \]

2. **Identify the Volumes of Reactants:**
According to the question, we have:
- 10 volumes of dihydrogen (H₂)
- 5 volumes of dioxygen (O₂)

3. **Determine the Stoichiometric Ratios:**
From the balanced equation, we see that:
- 2 volumes of H₂ react with 1 volume of O₂ to produce 2 volumes of H₂O.
- Therefore, 10 volumes of H₂ would require:
\[ \text{Required O}_2 = \frac{10 \text{ volumes of } H_2}{2} = 5 \text{ volumes of } O_2 \]
This means that 10 volumes of H₂ will completely react with 5 volumes of O₂.

4. **Calculate the Volume of Water Vapor Produced:**
According to the balanced equation, 2 volumes of H₂ produce 2 volumes of H₂O. Thus, 10 volumes of H₂ will produce:
\[ \text{Produced H}_2O = 10 \text{ volumes of } H_2O \]

5. **Conclusion:**
Therefore, the final answer is that 10 volumes of water vapor will be produced.

### Final Answer:
**10 volumes of water vapor will be produced.**

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