Which of the following have a triple bond?

Options

A. `C_(2)H_(4)`
B. `C_(3)H_(4)`
C. `CV_(3)H_(8)`
D. `C_(2)H_(6)`

Explanation

To determine which of the given compounds has a triple bond, we need to understand the classification of hydrocarbons based on their bonding.

### Step-by-Step Solution:

1. **Identify Hydrocarbon Types**:
- Hydrocarbons can be classified into three main categories based on the type of bonds they contain:
- **Alkanes**: These have only single bonds (general formula: CnH2n+2).
- **Alkenes**: These have at least one double bond (general formula: CnH2n).
- **Alkynes**: These have at least one triple bond (general formula: CnH2n-2).

2. **Use the General Formula for Alkynes**:
- The general formula for alkynes is CnH2n-2. This means that for every n carbon atoms, there are 2n-2 hydrogen atoms.
- For example, if n = 2 (2 carbon atoms), then the number of hydrogen atoms would be 2(2) - 2 = 2. Thus, the compound would be C2H2, which is an alkyne (ethyne or acetylene).

3. **Check Given Examples**:
- If we consider C3H4:
- Here, n = 3, so the number of hydrogen atoms would be 2(3) - 2 = 4. This fits the formula for alkynes, indicating that C3H4 has a triple bond.
- If we consider C3H8:
- Here, n = 3, so the number of hydrogen atoms would be 2(3) + 2 = 8. This fits the formula for alkanes, indicating that C3H8 has only single bonds.
- If we consider C2H6:
- Here, n = 2, so the number of hydrogen atoms would be 2(2) + 2 = 6. This also fits the formula for alkanes.

4. **Conclusion**:
- Based on the analysis, the compound that has a triple bond is C3H4, which is classified as an alkyne.

### Final Answer:
- The compound that has a triple bond is **C3H4 (an alkyne)**.