How many `pi` and `sigma` bonds are in the given compound?
`HC-=C-CH=CH_(2)`

Options

A. `3pi` and `6sigma` bonds
B. `3pi` and `7sigma` bonds
C. `2pi` and `7sigma` bonds
D. `4pi` and `8sigma` bonds

Answer

To determine the number of sigma (σ) and pi (π) bonds in the compound \( HC \equiv C - CH = CH_2 \), we will analyze the structure of the compound step by step.

### Step 1: Draw the Structure
The compound can be represented as follows:
- The first carbon (C1) is connected to one hydrogen (H) and has a triple bond with the second carbon (C2).
- The second carbon (C2) is connected to C1 with a triple bond and to the third carbon (C3) with a single bond.
- The third carbon (C3) is connected to C2 with a single bond and has a double bond with the fourth carbon (C4).
- The fourth carbon (C4) is connected to C3 with a double bond and has two hydrogens (H).

The structure can be visualized as:
```
H H
| |
H - C ≡ C - C = C - H
```

### Step 2: Count the Sigma Bonds
- Each single bond (C-H or C-C) is a sigma bond.
- Each double bond consists of one sigma bond and one pi bond.
- Each triple bond consists of one sigma bond and two pi bonds.

Now, let's count:
1. **C1 to H**: 1 σ bond
2. **C1 to C2 (triple bond)**: 1 σ bond
3. **C2 to C3**: 1 σ bond
4. **C3 to C4 (double bond)**: 1 σ bond
5. **C4 to H**: 1 σ bond

Total σ bonds:
- From C1 to H: 1
- From C1 to C2: 1
- From C2 to C3: 1
- From C3 to C4: 1
- From C4 to H: 1

Total σ bonds = 5

### Step 3: Count the Pi Bonds
Now, let's count the pi bonds:
1. **C1 to C2 (triple bond)**: 2 π bonds
2. **C3 to C4 (double bond)**: 1 π bond

Total π bonds:
- From C1 to C2: 2
- From C3 to C4: 1

Total π bonds = 3

### Final Count
- Total σ bonds = 5
- Total π bonds = 3

### Conclusion
The compound \( HC \equiv C - CH = CH_2 \) has **5 sigma bonds and 3 pi bonds**.