Vapour density

Options

A. decreases with incease in temperature
B. increases with increase in temperature
C. does not change with change in temperature
D. may increase or decrease with change in temperature

Explanation

To solve the question regarding vapor density and its relationship with temperature, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Vapor Density**:
- Vapor density is defined as the mass of a certain volume of gas compared to the mass of an equal volume of hydrogen at the same temperature and pressure. It is mathematically expressed as:
\[ \text{Vapor Density} = \frac{\text{Molar Mass}}{2} \]

2. **Identify the Relationship with Temperature**:
- From the formula, we can see that vapor density depends on the molar mass of the gas. The molar mass is a constant for a given substance and does not change with temperature.

3. **Analyze the Options Given**:
- The options provided are:
a) Decreases with an increase in temperature
b) Increases with an increase in temperature
c) Does not change with change in temperature
d) May increase or decrease with change in temperature

4. **Conclusion Based on the Concept**:
- Since vapor density is dependent only on the molar mass and is independent of temperature, the correct answer is:
\[ \text{c) Does not change with change in temperature} \]

### Final Answer:
The vapor density does not change with a change in temperature.

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