The number of sigma and pi-bonds present in 1, 3-butadiene are respectively
(a) 9 and 2
(b) 8 and 2
(c) 9 and 3
(d) 9 and 1
(e) 8 and 1

Explanation

To determine the number of sigma and pi bonds in 1,3-butadiene, we can follow these steps:

### Step 1: Draw the Structure of 1,3-Butadiene
1,3-butadiene has four carbon atoms with a double bond between the first and second carbon atoms, and another double bond between the third and fourth carbon atoms. The structure can be represented as follows:

```
H H H H
| | | |
H - C = C - C = C - H
| | | |
H H H H
```

### Step 2: Count the Sigma Bonds
- **C-H Bonds**: Each carbon atom is bonded to hydrogen atoms. In 1,3-butadiene:
- The first carbon (C1) has 2 hydrogen atoms (2 C-H sigma bonds).
- The second carbon (C2) has 1 hydrogen atom (1 C-H sigma bond).
- The third carbon (C3) has 1 hydrogen atom (1 C-H sigma bond).
- The fourth carbon (C4) has 2 hydrogen atoms (2 C-H sigma bonds).

Total C-H sigma bonds = 2 + 1 + 1 + 2 = 6 C-H sigma bonds.

- **C-C Bonds**: There are three C-C bonds in the structure:
- C1 to C2 (1 sigma bond)
- C2 to C3 (1 sigma bond)
- C3 to C4 (1 sigma bond)

Total C-C sigma bonds = 3.

- **Total Sigma Bonds**:
Total sigma bonds = C-H sigma bonds + C-C sigma bonds = 6 + 3 = 9 sigma bonds.

### Step 3: Count the Pi Bonds
- Each double bond consists of one sigma bond and one pi bond. In 1,3-butadiene, there are two double bonds:
- One between C1 and C2 (1 pi bond)
- One between C3 and C4 (1 pi bond)

- **Total Pi Bonds**:
Total pi bonds = 2 (one from each double bond).

### Conclusion
- The total number of sigma bonds in 1,3-butadiene is 9.
- The total number of pi bonds in 1,3-butadiene is 2.

Thus, the answer is:
**(a) 9 and 2.**