When chlorine in excess is treated with ammonia, the product formed is used as

Options

A. antipyretic
B. explosive
C. analgesic
D. laboratory agent

Explanation

To solve the question "When chlorine in excess is treated with ammonia, the product formed is used as," we need to analyze the reaction between chlorine and ammonia.

### Step-by-Step Solution:

1. **Identify the Reactants**: The reactants in this reaction are chlorine (Cl2) and ammonia (NH3).

2. **Understand the Reaction**: When chlorine is treated with ammonia in excess, they undergo a chemical reaction. The primary products of this reaction are nitrogen trichloride (NCl3) and hydrochloric acid (HCl).

\[ \text{3 Cl}_2 + \text{2 NH}_3 \rightarrow \text{NCl}_3 + 3 \text{HCl} \]

3. **Balance the Reaction**: The above equation is balanced. We have 3 chlorine atoms from Cl2 reacting with 2 ammonia molecules to produce one molecule of nitrogen trichloride and three molecules of hydrochloric acid.

4. **Identify the Product**: The main product formed from this reaction is nitrogen trichloride (NCl3).

5. **Determine the Use of the Product**: Nitrogen trichloride (NCl3) is known to be highly explosive. This is due to the presence of chlorine in a +1 oxidation state, which makes it a good oxidizing agent. It can oxidize nitrogen to form stable nitrogen gas (N2), and this property contributes to its explosive nature.

6. **Select the Correct Option**: Based on the information above, the correct answer to the question is that the product formed (NCl3) is used as an explosive.

### Final Answer:
The product formed when chlorine in excess is treated with ammonia is used as an **explosive** (Option B).

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