During an adiabatic change, specific heat of a gas is

Options

A. Zero
B. Positive
C. negative
D. infinity

Explanation

To solve the question regarding the specific heat of a gas during an adiabatic change, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Adiabatic Change**:
- An adiabatic process is defined as a process in which no heat is exchanged with the surroundings. This means that the change in heat (\( \Delta Q \)) is equal to zero.

\[ \Delta Q = 0 \]

2. **Relating Specific Heat to Heat Transfer**:
- The specific heat (\( c \)) of a substance is defined by the equation:

\[ \Delta Q = mc\Delta T \]

where:
- \( m \) is the mass of the gas,
- \( c \) is the specific heat,
- \( \Delta T \) is the change in temperature.

3. **Substituting for Adiabatic Process**:
- Since we know that \( \Delta Q = 0 \) for an adiabatic process, we can substitute this into the specific heat equation:

\[ 0 = mc\Delta T \]

4. **Analyzing the Equation**:
- For the equation \( mc\Delta T = 0 \) to hold true, either \( m = 0 \) (which is not the case as we have a gas) or \( c = 0 \) when \( \Delta T \) is not zero.
- Therefore, during an adiabatic change, the specific heat \( c \) must be zero.

5. **Conclusion**:
- The specific heat of a gas during an adiabatic change is zero. Thus, the correct answer is:

\[ \text{Specific heat during an adiabatic change is } 0. \]

### Final Answer:
The specific heat of a gas during an adiabatic change is **zero**.

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