Which of the following is independent of temperature?

Options

A. normality
B. molarity
C. molality
D. All of above

Explanation

To determine which concentration term is independent of temperature, we need to analyze the definitions of the concentration terms provided.

### Step-by-Step Solution:

1. **Understand the Concentration Terms**:
- Concentration terms include normality, molarity, molality, and others. Each of these terms has a specific definition related to the amount of solute and the volume or mass of the solution or solvent.

2. **Identify the Relationship with Volume**:
- Concentration terms that involve volume (like molarity and normality) are affected by temperature changes because temperature can cause the volume of a liquid to expand or contract.
- For example, molarity is defined as moles of solute per liter of solution (which involves volume), and normality is defined as equivalents of solute per liter of solution (also volume-dependent).

3. **Examine Molality**:
- Molality, on the other hand, is defined as the number of moles of solute per kilogram of solvent. This definition does not involve the volume of the solution, but rather the mass of the solvent.
- Since mass does not change with temperature, molality remains constant regardless of temperature changes.

4. **Conclusion**:
- Therefore, the concentration term that is independent of temperature is **molality**.

### Final Answer:
**Molality is independent of temperature.**