The strength of a solution (S) in gram/litre, is related to its normality (N) and equivalent weight of solute (E) by the formula

Options

A. `S=(N)/(E)`
B. `S=(E)/(N)`
C. `S=N.E.`
D. All of these

Explanation

To derive the relationship between the strength of a solution (S), its normality (N), and the equivalent weight of the solute (E), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Definitions**:
- The strength of a solution (S) is defined as the mass of solute (in grams) per liter of solution.
- Normality (N) is defined as the number of equivalents of solute per liter of solution.
- Equivalent weight (E) is the mass of solute that will combine with or displace one mole of hydrogen ions (H⁺) or one mole of electrons in a redox reaction.

2. **Writing the Formula for Normality**:
- The formula for normality (N) can be expressed as:
\[ N = \frac{W}{E \times V} \]
where:
- \( W \) = weight of solute in grams,
- \( E \) = equivalent weight of the solute,
- \( V \) = volume of solution in liters.

3. **Relating Strength to Weight**:
- The strength of the solution (S) can be expressed as:
\[ S = \frac{W}{V} \]
where \( V \) is the volume of the solution in liters.

4. **Substituting Strength into the Normality Formula**:
- Since \( W = S \times V \), we can substitute this into the normality formula:
\[ N = \frac{S \times V}{E \times V} \]
- The volume \( V \) cancels out:
\[ N = \frac{S}{E} \]

5. **Rearranging the Formula**:
- To express strength (S) in terms of normality (N) and equivalent weight (E), we rearrange the equation:
\[ S = N \times E \]

### Final Formula:
Thus, the relationship between strength (S), normality (N), and equivalent weight (E) is given by:
\[ S = N \times E \]