Compound (X) on complete catalytic hydrogenation with `H_2//Pt` gives an alkane. The number of moles of `H_2` required per mole of compound (X) is:

Options

A. 2
B. 3
C. 4
D. 5

Explanation

To determine the number of moles of hydrogen (H₂) required for the complete catalytic hydrogenation of compound (X) to form an alkane, we need to follow these steps:

### Step 1: Understand the Concept of Degree of Unsaturation
The degree of unsaturation (DU) indicates the number of hydrogen atoms that are missing from a saturated hydrocarbon. Each degree of unsaturation corresponds to one double bond or one ring in the structure of the compound.

### Step 2: Determine the Molecular Formula
We need to identify the number of carbon (C) and hydrogen (H) atoms in compound (X). According to the video transcript, compound (X) has:
- Number of Carbon (C) = 6
- Number of Hydrogen (H) = 6

### Step 3: Calculate the Degree of Unsaturation
The formula to calculate the degree of unsaturation is:
\[ \text{DU} = \frac{2C + 2 - H}{2} \]
Where:
- C = number of carbon atoms
- H = number of hydrogen atoms

Substituting the values:
\[ \text{DU} = \frac{2(6) + 2 - 6}{2} \]
\[ \text{DU} = \frac{12 + 2 - 6}{2} \]
\[ \text{DU} = \frac{8}{2} = 4 \]

### Step 4: Relate Degree of Unsaturation to Hydrogen Requirement
For each degree of unsaturation, one mole of H₂ is required for complete hydrogenation. Therefore, the number of moles of hydrogen required is equal to the degree of unsaturation.

### Step 5: Conclusion
Since the degree of unsaturation (DU) is 4, the number of moles of hydrogen (H₂) required for the complete hydrogenation of compound (X) is:
\[ \text{Number of moles of } H_2 = \text{DU} = 4 \]

Thus, the final answer is that 4 moles of H₂ are required per mole of compound (X).