Which statement of the following is incorrect for gases ?

Options

A. Volume of the gas is equal to the volume of the container confining the gas
B. Confined gas exerts uniform pressure on the walls of its container in all directions
C. Gases do not have a definite shape and volume
D. Mass of the gas cannot gas cannot be determined by weighing a container in which it is enclosed

Answer

To determine which statement is incorrect for gases, let's analyze each option step by step.

### Step 1: Analyze the first statement
**Statement:** The volume of the gas is equal to the volume of the container confining the gas.

**Analysis:**
- Gases expand to fill the entire volume of their container.
- Therefore, this statement is true.

### Step 2: Analyze the second statement
**Statement:** Confined gas exerts uniform pressure on the walls of the container in all directions.

**Analysis:**
- Gas molecules move randomly and collide with the walls of the container.
- Due to these collisions, the pressure exerted by the gas is uniform in all directions.
- Hence, this statement is also true.

### Step 3: Analyze the third statement
**Statement:** Gases do not have a definite shape and volume.

**Analysis:**
- Gases take the shape of their container and do not have a fixed volume.
- This statement is true as well.

### Step 4: Analyze the fourth statement
**Statement:** The mass of gas cannot be determined by weighing a container in which it is enclosed.

**Analysis:**
- The mass of a gas can indeed be determined by weighing the container with the gas and then subtracting the weight of the empty container.
- Therefore, this statement is incorrect.

### Conclusion
The incorrect statement regarding gases is: **The mass of gas cannot be determined by weighing a container in which it is enclosed.**

### Final Answer
The answer is option D.

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