Which of the following reagents are used for detecting the presence of carbonyl group?

Options

A. `NH_(2)OH`
B. `NH_(2)NH_(2)`
C. `H_(2)NCONHNH_(2).HCl`
D. `C_(6)H_(5)NHNH_(2).HCl`

Answer

To determine which reagents are used for detecting the presence of a carbonyl group (C=O), we can follow these steps:

### Step 1: Understand the Carbonyl Group
The carbonyl group is characterized by a carbon atom double-bonded to an oxygen atom (C=O). It is present in aldehydes and ketones.

### Step 2: Identify Common Reagents for Carbonyl Detection
Several reagents are commonly used to detect carbonyl groups. Some of these include:
- **2,4-Dinitrophenylhydrazine (DNPH)**: Forms a yellow or orange precipitate with carbonyl compounds.
- **Hydroxylamine**: Reacts with carbonyl groups to form oximes.
- **Tollens' Reagent**: Used specifically for aldehydes, it produces a silver mirror effect.
- **Fehling's Solution**: Used for detecting aldehydes, it forms a brick-red precipitate.

### Step 3: Analyze the Given Reagents
From the video transcript, the reagents mentioned are:
- **Hydroxylamine (NH2OH)**
- **Hydrazine (N2H4)**

Both of these reagents can be used to detect carbonyl groups. Hydroxylamine forms oximes with carbonyl compounds, while hydrazine can form hydrazones.

### Step 4: Conclusion
The reagents used for detecting the presence of carbonyl groups include:
1. Hydroxylamine
2. 2,4-Dinitrophenylhydrazine
3. Tollens' Reagent
4. Fehling's Solution

### Final Answer
The reagents that are used for detecting the presence of carbonyl groups are Hydroxylamine and Hydrazine, among others like DNPH, Tollens' Reagent, and Fehling's Solution.

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