A 100 ml aq. Solution of NaCl contains 20 gm of NaCl. Find (w/v)%

Answer

To find the weight/volume percentage (w/v%) of a solution, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the mass of the solute (NaCl)**:
- Given mass of NaCl = 20 grams.

2. **Identify the volume of the solution**:
- Given volume of the solution = 100 ml.

3. **Use the formula for weight/volume percentage**:
- The formula for w/v% is:
\[ \text{w/v\%} = \left( \frac{\text{mass of solute (g)}}{\text{volume of solution (ml)}} \right) \times 100 \]

4. **Substitute the values into the formula**:
- Substitute the mass of NaCl and the volume of the solution into the formula:
\[ \text{w/v\%} = \left( \frac{20 \text{ g}}{100 \text{ ml}} \right) \times 100 \]

5. **Calculate the value**:
- Perform the calculation:
\[ \text{w/v\%} = \left( \frac{20}{100} \right) \times 100 = 0.2 \times 100 = 20\% \]

6. **Final answer**:
- The weight/volume percentage (w/v%) of the NaCl solution is **20%**.