How many `sigma` and `pi` bonds are present in the molecule of ethene ?

Answer

To determine the number of sigma (σ) and pi (π) bonds in the molecule of ethene (C₂H₄), we can follow these steps:

### Step 1: Understand the Structure of Ethene
Ethene is a simple hydrocarbon with the formula C₂H₄. It consists of two carbon atoms and four hydrogen atoms. The structure of ethene can be represented as:

```
H H
\ /
C = C
/ \
H H
```

### Step 2: Identify the Types of Bonds
In ethene, there is a double bond between the two carbon atoms. A double bond consists of one sigma bond and one pi bond. Additionally, each carbon atom is bonded to two hydrogen atoms through single bonds.

### Step 3: Count the Sigma Bonds
1. **C-C Bond**: The double bond between the two carbon atoms contributes **1 sigma bond**.
2. **C-H Bonds**: Each carbon atom is bonded to two hydrogen atoms. Since there are two carbon atoms, this contributes **4 sigma bonds** (2 from each carbon).

Total sigma bonds = 1 (C-C) + 4 (C-H) = **5 sigma bonds**.

### Step 4: Count the Pi Bonds
The double bond between the two carbon atoms also contributes **1 pi bond**.

### Final Count
- **Total Sigma Bonds**: 5
- **Total Pi Bonds**: 1

### Conclusion
In the molecule of ethene (C₂H₄), there are **5 sigma bonds** and **1 pi bond**.

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