Which of the following compounds has a double bond?

Options

A. `C_14 H_28`
B. `C_15 H_32`
C. `C_12 H_22`
D. `C_16 H_34`

Explanation

To determine which of the given compounds has a double bond, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Types of Hydrocarbons**:
- Alkanes: Compounds with only single bonds. General formula: \( C_nH_{2n+2} \)
- Alkenes: Compounds with at least one double bond. General formula: \( C_nH_{2n} \)
- Alkynes: Compounds with at least one triple bond. General formula: \( C_nH_{2n-2} \)

2. **Identify the General Formulas**:
- For alkenes, the number of hydrogen atoms is exactly double the number of carbon atoms (minus 2).
- For alkanes, the number of hydrogen atoms is double the number of carbon atoms plus 2.
- For alkynes, the number of hydrogen atoms is double the number of carbon atoms minus 2.

3. **Analyze Each Option**:
- For each compound provided in the options, calculate the number of hydrogen atoms based on the number of carbon atoms and see which formula it fits.
- If the formula fits \( C_nH_{2n} \), then it is an alkene and has a double bond.

4. **Example Calculation**:
- Suppose we have a compound with 14 carbon atoms:
- Calculate hydrogen: \( H = 2n \) where \( n = 14 \)
- \( H = 2 \times 14 = 28 \)
- This matches the alkene formula \( C_{14}H_{28} \), indicating a double bond is present.
- For another compound with 14 carbon atoms and 30 hydrogen atoms:
- Calculate hydrogen: \( H = 2n + 2 \) where \( n = 14 \)
- \( H = 2 \times 14 + 2 = 30 \)
- This matches the alkane formula, indicating no double bond.

5. **Conclusion**:
- After analyzing all options, identify the compound that fits the alkene formula \( C_nH_{2n} \) as the one with a double bond.