A gas in an airtight container is heated from `25^(@)C ` to `90^(@)C`. The density of gas will

Options

A. (a)increase slightly
B. (b)increase considerably
C. (c)remain the same
D. (d)decrease slightly

Answer

To solve the problem of how the density of a gas in an airtight container changes when heated from 25°C to 90°C, we can follow these steps:

### Step 1: Understand the Concept of Density
Density (D) is defined as the mass (m) of a substance divided by its volume (V):
\[ D = \frac{m}{V} \]

### Step 2: Analyze the Conditions
In this case, we have an airtight container. This means that:
- The mass of the gas inside the container remains constant because no gas can enter or escape.
- The volume of the gas also remains constant because the container is rigid and airtight.

### Step 3: Consider the Effect of Temperature
When the gas is heated from 25°C to 90°C, we need to consider how temperature affects the gas:
- Generally, heating a gas causes it to expand. However, since the volume is constant in an airtight container, the gas cannot expand.

### Step 4: Determine the Impact on Density
Since both the mass and volume of the gas remain constant:
- The density of the gas can be expressed as:
\[ D = \frac{m}{V} \]
- As both m (mass) and V (volume) are constant, the density (D) does not change.

### Conclusion
Therefore, the density of the gas will remain the same when heated from 25°C to 90°C in an airtight container.

### Final Answer
The density of the gas will remain the same.

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