100 mL of a sample of tap water requires 50 mL of `N // 50-` HCl solution for titration.
Calculate the temporary hardness of tap water.

Explanation

To calculate the temporary hardness of tap water in parts per million (ppm), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Given Data:**
- Volume of tap water sample = 100 mL
- Volume of HCl solution used for titration = 50 mL
- Normality of HCl solution = \( \frac{1}{50} \) N
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