Which one of the following properties of a gas is not consistent with kinetic theory?

Options

A. The average speed of the gas molecules is smaller at high temperatures.
B. Gas molecules are widely separated.
C. Gases fill whatever space is available to them.
D. Gas molecules move rapidly in a random fashion.

Answer

To determine which property of a gas is not consistent with the kinetic theory, we need to analyze the assumptions of the kinetic theory of gases. Here’s a step-by-step solution:

### Step 1: Understand the Kinetic Theory of Gases
The kinetic theory of gases is based on several assumptions about the behavior of gas molecules. It describes how gas particles move and interact with each other.

### Step 2: Analyze the Properties of Gases
We need to evaluate the following properties of gases in relation to the kinetic theory:
1. Average speed of gas molecules is smaller at high temperature.
2. Gas molecules are widely separated.
3. The volume of the gas is the same as the volume of the container.
4. Gas molecules exhibit random motion.

### Step 3: Evaluate Each Property
1. **Average Speed and Temperature**: According to the kinetic theory, the average speed of gas molecules increases with an increase in temperature. Therefore, the statement that the average speed is smaller at high temperature is **incorrect**.

2. **Widely Separated Molecules**: The kinetic theory assumes that gas molecules are widely separated, especially under low pressure and high temperature conditions. This statement is **consistent** with kinetic theory.

3. **Volume of Gas and Container**: The kinetic theory assumes that gases occupy the volume of their container. This statement is also **consistent** with kinetic theory.

4. **Random Motion**: The kinetic theory posits that gas molecules move in random directions and speeds. This statement is **consistent** with kinetic theory.

### Step 4: Identify the Incorrect Property
From the analysis, the only property that contradicts the kinetic theory is the first one: "Average speed of gas molecules is smaller at high temperature." Therefore, this is the property that is **not consistent** with the kinetic theory.

### Conclusion
The property of a gas that is not consistent with kinetic theory is:
**The average speed of gas molecules is smaller at high temperature.**

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