Colligative properties are used for the determination of

Options

A. molar mass
B. equivalent mass
C. arrangement of molecules
D. melting and boiling points

Answer

**Step-by-Step Solution:**

1. **Understanding Colligative Properties:**
- Colligative properties are properties of solutions that depend on the number of solute particles in a given amount of solvent, rather than the identity of the solute. This means that they are influenced by the concentration of solute particles.

2. **Types of Colligative Properties:**
- The main colligative properties include:
- Vapor pressure lowering
- Boiling point elevation
- Freezing point depression
- Osmotic pressure

3. **Determining Molar Mass:**
- Colligative properties can be used to determine the molar mass of a solute. This is done by measuring the change in boiling point or freezing point when a known amount of solute is dissolved in a solvent. The extent of the change is directly related to the number of solute particles.

4. **Evaluating the Options:**
- Option A: Molar mass - This is correct because colligative properties can be used to calculate the molar mass of a solute.
- Option B: Equivalent mass - This is incorrect as colligative properties do not directly provide information about equivalent mass.
- Option C: Arrangement of molecules - This is incorrect because colligative properties do not provide information about the arrangement of molecules.
- Option D: Melting and boiling point - This is partially correct; however, colligative properties measure the change in these points rather than providing the values directly.

5. **Conclusion:**
- Based on the evaluation of the options, the correct answer is that colligative properties are used for the determination of **molar mass**.

**Final Answer:**
Colligative properties are used for the determination of **molar mass**.

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