In the given reaction `(A)+(B)overset(NaOH//Delta)rarrC_6H_5-CH=CH-CHO` A and B will be

Options

A. `C_6H_5 CHO and HCHO`
B. `C_6H_5CHO and CH_3CH_2-CHO`
C. `C_6H_5-CHO and CH_3-CHO`
D. `C_6H_5-CH_2-CHO and CH_3-CHO`

Answer

To solve the problem, we need to identify the compounds A and B that react together in the presence of sodium hydroxide (NaOH) and heat to form the product \( C_6H_5-CH=CH-CHO \). Here’s a step-by-step breakdown of the solution:

### Step 1: Analyze the Product
The product is \( C_6H_5-CH=CH-CHO \), which is an α,β-unsaturated aldehyde. This indicates that it has a double bond between the second and third carbon atoms, with the aldehyde group at the end.

### Step 2: Identify the Reaction Type
The reaction involves aldol condensation, which typically requires two aldehyde or ketone molecules. In this case, since we have an aldehyde as the product, we can infer that both reactants A and B are likely aldehydes.

### Step 3: Determine the Structure of A and B
To form the product \( C_6H_5-CH=CH-CHO \) through aldol condensation, we can deduce the structures of A and B.

1. The product contains a phenyl group \( C_6H_5 \) attached to a carbon chain. This suggests that one of the reactants (let's say A) is likely to be benzaldehyde \( C_6H_5CHO \).
2. The other reactant (B) must provide the necessary carbon chain to complete the product. The remaining part of the product \( CH=CH-CHO \) suggests that B is likely to be acetaldehyde \( CH_3CHO \).

### Step 4: Write the Reaction
The aldol condensation reaction can be written as:
\[ C_6H_5CHO + CH_3CHO \overset{NaOH, \Delta}{\rightarrow} C_6H_5-CH=CH-CHO + H_2O \]

### Conclusion
Thus, the compounds A and B are:
- A: Benzaldehyde \( C_6H_5CHO \)
- B: Acetaldehyde \( CH_3CHO \)

### Final Answer
A and B will be:
- A: Benzaldehyde \( C_6H_5CHO \)
- B: Acetaldehyde \( CH_3CHO \)

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