Write the chemical test to identify the following gases.
HCl

Explanation

To identify the presence of hydrochloric acid (HCl) gas, you can perform the following chemical test:

### Step-by-Step Solution:

1. **Prepare the Apparatus**: Gather the necessary materials, including a test tube, a dropper, and an aqueous solution of silver nitrate (AgNO3).

2. **Pass HCl Gas through Silver Nitrate Solution**: Introduce HCl gas into the test tube containing the aqueous silver nitrate solution. This can be done by bubbling the gas through the solution.

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