Write the general formula of alkenes. Give `IUPAC` names of first three members.

Answer

To solve the question, we need to follow these steps:

### Step 1: Identify the General Formula of Alkenes
The general formula for alkenes can be derived from their structure. Alkenes are hydrocarbons that contain at least one carbon-carbon double bond. The general formula for alkenes is:

\[ C_nH_{2n} \]

where \( n \) is the number of carbon atoms.

### Step 2: List the First Three Members of Alkenes
Now, we will identify the first three members of the alkene family based on the general formula:

1. **For n = 1**:
- \( C_1H_2 \) (This is not a valid alkene as it cannot exist with only one carbon atom.)

2. **For n = 2**:
- \( C_2H_4 \)
- IUPAC Name: Ethene

3. **For n = 3**:
- \( C_3H_6 \)
- IUPAC Name: Propene

4. **For n = 4**:
- \( C_4H_8 \)
- IUPAC Name: Butene

### Step 3: Summarize the Results
The general formula for alkenes is \( C_nH_{2n} \). The first three members of the alkene series, along with their IUPAC names, are:

1. Ethene (C2H4)
2. Propene (C3H6)
3. Butene (C4H8)

### Final Answer
- **General Formula of Alkenes**: \( C_nH_{2n} \)
- **IUPAC Names of the First Three Members**:
1. Ethene (C2H4)
2. Propene (C3H6)
3. Butene (C4H8)

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