The active mass of solid is generally taken as

Options

A. `gt 1`
B. `=1`
C. ` lt 1`
D. 0

Answer

To solve the question regarding the active mass of a solid, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Active Mass**:
- Active mass refers to the concentration of reactants and products in a chemical reaction, typically expressed in moles per liter (mol/L).

2. **Active Mass of Solids**:
- In the context of solids, their active mass is considered to be constant during a reaction because the concentration of a solid does not change significantly as it is present in a fixed amount.

3. **Value of Active Mass for Solids**:
- The active mass of a solid is conventionally taken as 1. This is because, in the context of equilibrium expressions, solids do not appear in the expression for the equilibrium constant. Their concentration is treated as a constant.

4. **Conclusion**:
- Therefore, the active mass of a solid is taken as equal to 1.

5. **Identifying the Correct Option**:
- Based on the above reasoning, we can conclude that the correct answer to the question is option B, which states that the active mass of a solid is equal to 1.

### Final Answer:
The active mass of solid is generally taken as **1**.

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