Which of the statements are correct for alkyne with molecular
formula `C_6H_(10)`?

Options

A. (a) It shows 7 structural isomers.
B. (b) It shows 4 terminal and 3 internal alkynes.
C. (c) It shows 3 terminal and 4 internal alkynes.
D. (d) Only one isomer is chiral.

Explanation

To determine which statements are correct for the alkyne with the molecular formula C₆H₁₀, we will analyze the possible structures and characteristics of this compound step by step.

### Step 1: Identify the General Structure of Alkynes
Alkynes are hydrocarbons that contain at least one carbon-carbon triple bond. The general formula for alkynes is CₙH₂ₙ₋₂. For C₆H₁₀, we can confirm that it is indeed an alkyne since it fits the formula.

### Step 2: Draw Possible Isomers
We need to draw the structural isomers for C₆H₁₀. We can have both terminal and internal alkynes.

1. **Terminal Alkyne**: The triple bond is at the end of the carbon chain.
- Example: Hex-1-yne (C≡C at the first position).
- Example: 4-Methylpent-1-yne (C≡C at the first position with a methyl group at the fourth position).
- Example: 3-Methylpent-1-yne (C≡C at the first position with a methyl group at the third position).
- Example: 3,3-Dimethylbut-1-yne (C≡C at the first position with two methyl groups at the third position).

2. **Internal Alkyne**: The triple bond is between carbon atoms in the chain.
- Example: Hex-2-yne (C≡C at the second position).
- Example: Hex-3-yne (C≡C at the third position).
- Example: 4-Methylpent-2-yne (C≡C at the second position with a methyl group at the fourth position).

### Step 3: Count the Isomers
From the structures drawn, we can identify:
- **Total Isomers**: 7
- 4 Terminal Alkynes
- 3 Internal Alkynes

### Step 4: Identify Chiral Centers
A chiral center is a carbon atom that has four different substituents. In our structures:
- **Chiral Isomer**: 3-Methylpent-1-yne has one chiral center.

### Step 5: Evaluate the Statements
Now, we can evaluate the statements provided:
1. **It shows seven structural isomers**: **Correct**
2. **It shows four terminal and three internal**: **Correct**
3. **It shows three chiral isomers**: **Incorrect** (there is only one chiral isomer)
4. **Only one isomer is chiral**: **Correct**

### Conclusion
The correct statements regarding the alkyne with the molecular formula C₆H₁₀ are:
- A: It shows seven structural isomers (Correct)
- B: It shows four terminal and three internal (Correct)
- C: It shows three chiral isomers (Incorrect)
- D: Only one isomer is chiral (Correct)

Thus, the correct answers are A, B, and D.

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