Boiling water is changing into steam. Under this condition the specific heat of water is

Options

A. zero
B. one
C. infinite
D. less than one

Answer

To solve the question regarding the specific heat of boiling water changing into steam, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Process**:
- When water boils, it undergoes a phase change from liquid to gas (steam) at a constant temperature. This process occurs at the boiling point of water (100°C at standard atmospheric pressure).

2. **Specific Heat Formula**:
- The specific heat capacity (c) is defined by the formula:
\[ q = mc\Delta T \]
where:
- \( q \) = heat added or removed,
- \( m \) = mass of the substance,
- \( c \) = specific heat capacity,
- \( \Delta T \) = change in temperature.

3. **Identifying the Conditions**:
- In the case of boiling water turning into steam, the temperature remains constant during the phase change. Therefore, the change in temperature (\( \Delta T \)) is 0.

4. **Substituting into the Formula**:
- If we substitute \( \Delta T = 0 \) into the specific heat formula, we get:
\[ c = \frac{q}{m \Delta T} = \frac{q}{m \times 0} \]
- Since division by zero is undefined, this implies that the specific heat capacity becomes infinite.

5. **Conclusion**:
- Therefore, the specific heat of boiling water under the condition of changing into steam is infinite.

### Final Answer:
The specific heat of boiling water is infinite when it is changing into steam.

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