An organic compound ("X") is a disubstituted benzene containing 77.8% carbon and 7.4 % hydrogen. Heating an alkaline solution of "X" with chloroform gives a steam volatile compound "Y" . Heating "Y" with acetic anhydride and sodium acetate gives a smelling crystalline solid "Z". "Z" is

Options

A.
B.
C.
D.

Answer

To solve the question step by step, we will analyze the information provided and deduce the structure of the compounds involved.

### Step 1: Determine the molecular formula of compound "X"
Given that compound "X" contains 77.8% carbon and 7.4% hydrogen, we can calculate the empirical formula.

1. **Calculate the percentage of oxygen**:
- Total percentage = 100%
- Percentage of oxygen = 100% - (77.8% + 7.4%) = 100% - 85.2% = 14.8%

2. **Convert percentages to moles**:
- Moles of Carbon (C) = 77.8 g / 12 g/mol = 6.48 mol
- Moles of Hydrogen (H) = 7.4 g / 1 g/mol = 7.4 mol
- Moles of Oxygen (O) = 14.8 g / 16 g/mol = 0.925 mol

3. **Divide by the smallest number of moles**:
- C: 6.48 / 0.925 = 7
- H: 7.4 / 0.925 = 8
- O: 0.925 / 0.925 = 1

Thus, the empirical formula is C7H8O, which suggests that compound "X" is likely a disubstituted benzene derivative, possibly toluene (C6H5-CH3) with an -OH group (phenol).

### Step 2: Identify compound "Y"
When compound "X" is heated with an alkaline solution and chloroform (CHCl3), it undergoes a reaction known as the Reimer-Tiemann reaction, which introduces an aldehyde group at the meta position relative to the hydroxyl group.

1. **Structure of compound "Y"**:
- The structure of "Y" would be a meta-hydroxybenzaldehyde (C7H6O), where the -CHO group is at the meta position to the -OH group.

### Step 3: Identify compound "Z"
When compound "Y" is heated with acetic anhydride and sodium acetate, it undergoes an acetylation reaction.

1. **Reaction with acetic anhydride**:
- The aldehyde group reacts with acetic anhydride to form an acylated product. The expected product is an aromatic compound with an acetyl group and a hydroxyl group.

2. **Structure of compound "Z"**:
- The resulting compound "Z" would be an aromatic compound with both an acetyl group (C=O) and a hydroxyl group (-OH), likely a derivative of salicylic acid or an acetylated phenol.

### Conclusion
Based on the reactions and transformations described, the final compound "Z" is likely to be **acetylsalicylic acid** (commonly known as aspirin), which is a crystalline solid with a distinct smell.

### Final Answer
The compound "Z" is **acetylsalicylic acid (aspirin)**.

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