With Nessler's reagent ammonia gives

Options

A. white precipitate
B. violet precipitate
C. blue precipitate
D. brown precipitate

Explanation

To solve the question "With Nessler's reagent, ammonia gives:", we need to understand the reaction that occurs when ammonia interacts with Nessler's reagent.

### Step-by-Step Solution:

1. **Identify Nessler's Reagent**:
Nessler's reagent is a solution of mercuric iodide (HgI2) in potassium iodide (KI). It is commonly used to detect the presence of ammonia in a solution.

2. **Write the Reaction**:
When ammonia (NH3) reacts with Nessler's reagent, it forms a complex. The balanced chemical reaction can be represented as:
\[ 2 \text{HgI}_2 + 2 \text{NH}_3 + 2 \text{KOH} \rightarrow \text{Hg}_2\text{(NH}_2\text{)}_2\text{I}_4 + 2 \text{K}_2\text{I} \]
In this reaction, the product formed is a colored precipitate.

3. **Determine the Color of the Precipitate**:
The precipitate formed when ammonia reacts with Nessler's reagent is typically a brown or reddish-brown color. This is due to the formation of a mercuric-ammonium complex.

4. **Choose the Correct Option**:
From the options given:
- A) White precipitate
- B) Violet precipitate
- C) Blue precipitate
- D) Brown precipitate

The correct answer is option D, which indicates that ammonia gives a brown precipitate with Nessler's reagent.

### Final Answer:
With Nessler's reagent, ammonia gives a **brown precipitate** (Option D).

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