Fill in the blanks by using the correct word/term given in the brackets.
The pH of water decreases when _____ is dissolved in it. `(NH_(3)//SO_(2))`

Explanation

To solve the question, we need to fill in the blank with the correct term from the options provided: `(NH₃ // SO₂)`.

### Step-by-Step Solution:

1. **Understanding pH**: The pH scale measures how acidic or basic a solution is. A pH of 7 is considered neutral (like pure water), a pH less than 7 indicates an acidic solution, and a pH greater than 7 indicates a basic solution.

2. **Analyzing the Options**:
- **Ammonia (NH₃)**: When ammonia is dissolved in water, it forms ammonium hydroxide (NH₄OH), which is a basic solution. Therefore, the pH of the solution increases and becomes greater than 7.
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