Choose the correct statement regarding equivalent weight

Options

A. Equivalent weight of a substance always remain same
B. Equivalent weight of substance depends on reaction
C. Equivalent weight may be greater than atomic weight
D. Equivalent weight may be less than atomic weight

Answer

To solve the question regarding equivalent weight, we need to analyze each of the provided statements carefully. Let's break it down step by step:

### Step 1: Understand the Concept of Equivalent Weight
Equivalent weight is defined as the mass of a substance that will combine with or displace 1 mole of hydrogen atoms or 1 mole of electrons in a reaction. It can be calculated using the formula:

\[ \text{Equivalent Weight} = \frac{\text{Molar Mass}}{n \text{ factor}} \]

Where the n factor represents the number of moles of reactive units (like H+ ions or electrons) that one mole of the substance can provide or react with.

### Step 2: Analyze Each Statement
1. **Statement 1**: "Equivalent weight of a substance always remains the same."
- This statement is **incorrect**. The equivalent weight can change depending on the reaction, as the n factor can vary.

2. **Statement 2**: "Equivalent weight of a substance depends on reaction."
- This statement is **correct**. Since the n factor changes with different reactions, the equivalent weight will also change.

3. **Statement 3**: "Equivalent weight may be greater than atomic weight."
- This statement is **incorrect**. The n factor cannot be less than 1, so the equivalent weight cannot exceed the molar mass.

4. **Statement 4**: "Equivalent weight may be less than atomic weight."
- This statement is **correct**. Since the n factor is always greater than or equal to 1, it is possible for the equivalent weight to be less than the atomic weight.

### Step 3: Conclusion
Based on the analysis, the correct statements regarding equivalent weight are:
- Statement 2: Equivalent weight of a substance depends on reaction.
- Statement 4: Equivalent weight may be less than atomic weight.

### Final Answer
The correct statements are **Statement 2 and Statement 4**.

---