In the reaction
X + Y `underset(5^(@)C)overset(NaOH)(rarr) CH_(3)-overset(OH)overset(|)(CH)-underset(CH_(3))underset(|)(CH)-CHO`
(X) and (Y) Will respectively be :

Options

A. `H_3C-CH_2-CHO and CH_3-CH_2-CHO`
B. `H_3C-CHO and CH_3-CH_2-CHO`
C. `H_3C-CHO and CH_3-CHO`
D. `H_3C-CHOand H_3C-underset(CH_3)underset(|)overset(OH)overset(|)C-CHO`

Answer

To solve the problem, we need to identify the compounds X and Y that react to form the given product in the presence of NaOH at 5°C. The product formed is:

\[ CH_3-CHOH-CH(CH_3)-CHO \]

This structure indicates that the product is an aldol, which contains both an aldehyde and an alcohol functional group. Let's break down the steps to identify X and Y.

### Step 1: Analyze the Product Structure
The product can be rewritten as:

\[ CH_3-CHOH-CH(CH_3)-CHO \]

This indicates that we have:
- An aldehyde group (CHO)
- An alcohol group (OH)

### Step 2: Identify Possible Aldehydes
Since the product is an aldol, we can infer that it is formed from two aldehydes. The aldehyde functional groups in the product suggest that they could be derived from simpler aldehydes.

### Step 3: Determine the Aldehydes
1. The product has a total of 4 carbon atoms in the aldehyde groups.
2. The structure suggests that one of the aldehydes could be acetaldehyde (ethanal, \( CH_3CHO \)).
3. The other aldehyde must be butanal (\( CH_3CH_2CHO \)), which has 4 carbon atoms.

### Step 4: Write the Reaction
The aldol condensation reaction can be represented as:

\[ CH_3CHO + CH_3CH_2CHO \xrightarrow{NaOH} CH_3-CHOH-CH(CH_3)-CHO \]

### Conclusion
Thus, the compounds X and Y are:
- **X = Acetaldehyde (\( CH_3CHO \))**
- **Y = Butanal (\( CH_3CH_2CHO \))**

### Final Answer
X and Y will respectively be:
- **X = Acetaldehyde (CH₃CHO)**
- **Y = Butanal (CH₃CH₂CHO)**

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