In the hydrocarbon
`underset(6)(CH_(3))-underset(5)(C) equiv underset(4)(CH) - underset(3)overset(CH_(3))overset(|)(CH) - underset(2)(C )equiv underset(1)(CH)`
the state of hybridizaton of carbon 1,3 and 5 are in the following sequence

Options

A. `sp^(3), sp^(2), sp`
B. `sp^(2) , sp , sp^(3)`
C. sp, `sp^(3), sp`
D. `sp, sp^(2), sp^(3)`

Answer

To determine the hybridization states of carbon atoms 1, 3, and 5 in the given hydrocarbon, we can follow these steps:

### Step 1: Identify the Structure
We need to visualize the structure of the hydrocarbon provided. The hydrocarbon is represented as:
```
CH
|
CH3 - C ≡ C - CH
|
CH3
```
This structure indicates that carbon 1 and carbon 5 are terminal carbons with single bonds to hydrogen, while carbon 3 is involved in a triple bond with carbon 2.

### Step 2: Analyze Carbon 1
Carbon 1 (C1) is bonded to three hydrogen atoms and one carbon atom. This means it forms four sigma bonds (3 with H and 1 with C).
- **Hybridization of Carbon 1**: Since it forms four sigma bonds, it is **sp³ hybridized**.

### Step 3: Analyze Carbon 3
Carbon 3 (C3) is involved in a triple bond with carbon 2 and has one hydrogen atom attached. In this case, it forms two sigma bonds (one with C2 and one with H) and two pi bonds (from the triple bond).
- **Hybridization of Carbon 3**: Since it forms two sigma bonds and two pi bonds, it is **sp hybridized**.

### Step 4: Analyze Carbon 5
Carbon 5 (C5) is similar to carbon 1. It is bonded to three hydrogen atoms and one carbon atom. This means it also forms four sigma bonds (3 with H and 1 with C).
- **Hybridization of Carbon 5**: Since it forms four sigma bonds, it is **sp³ hybridized**.

### Conclusion
The sequence of hybridization for carbon atoms 1, 3, and 5 is:
- Carbon 1: sp³
- Carbon 3: sp
- Carbon 5: sp³

Thus, the final answer is:
**sp³, sp, sp³**