`underset((C_4 H_8 Cl_2))A underset(373K)overset("Hydrolysis")to underset((C_4H_8 O))B`
B reacts with Hydroxyl amine but does not give Tollen's test . Identify A and B

Options

A. 1,1 Dichlorobutane and 2-Butanone
B. 2,2- Dichlorobutane and Butanal
C. 1,1 - Dichlorobutane and Butanal
D. 2,2-Dichlorobutane and 2-butane-one

Answer

To solve the problem, we need to identify the compounds A and B based on the given information.

1. **Identify Compound A (C₄H₈Cl₂)**:
- The molecular formula C₄H₈Cl₂ suggests that we have a dichlorinated butane.
- The most likely candidates for A are 1,2-Dichlorobutane or 2,2-Dichlorobutane.
- Since hydrolysis is mentioned, we will consider how each of these compounds would react with water.

2. **Hydrolysis of A**:
- Let's take 2,2-Dichlorobutane as our compound A. The structure is:
```
CH₃-CH(Cl)-C(Cl)-CH₃
```
- When hydrolyzed, water acts as a nucleophile and attacks the carbon bonded to the chlorine atoms, leading to the substitution of Cl with OH groups.
- The reaction proceeds as follows:
- The first water molecule attacks one of the Cl atoms, leading to the formation of an alcohol and HCl.
- The second water molecule will attack the other Cl, leading to the formation of a diol.
- However, two hydroxyl groups on one carbon are not stable, so dehydration occurs, forming a ketone.

3. **Identify Compound B (C₄H₈O)**:
- After hydrolysis, we get a compound with the formula C₄H₈O.
- The structure of the product would be:
```
CH₃-CO-CH₂-CH₃ (butan-2-one)
```
- This compound is a ketone, which does not have an aldehyde group.

4. **Tollen's Test**:
- The problem states that compound B does not give a Tollen's test. This is consistent because Tollen's test is used to identify aldehydes, and since B is a ketone, it will not react positively.

5. **Final Identification**:
- Therefore, we conclude:
- **Compound A** is **2,2-Dichlorobutane** (C₄H₈Cl₂).
- **Compound B** is **butan-2-one** (C₄H₈O).

### Summary:
- **A** = 2,2-Dichlorobutane (C₄H₈Cl₂)
- **B** = Butan-2-one (C₄H₈O)