Only triple bond is present in

Options

A. `N_2O`
B. `CO_2`
C. `HCN`
D. `N_2`

Answer

To determine which molecule contains only a triple bond, we will analyze the bonding structures of the given molecules: N2O, CO2, HCN, and N2.

### Step-by-Step Solution:

1. **Analyze N2O (Nitrous Oxide)**:
- The structure of N2O can be represented as N≡N-O or N=N=O.
- In both representations, there is a triple bond between the two nitrogen atoms and a single bond between nitrogen and oxygen.
- Conclusion: N2O has both a triple bond and a single bond. **Not the answer.**

2. **Analyze CO2 (Carbon Dioxide)**:
- The structure of CO2 is O=C=O.
- Here, carbon forms double bonds with both oxygen atoms.
- Conclusion: CO2 has only double bonds. **Not the answer.**

3. **Analyze HCN (Hydrogen Cyanide)**:
- The structure of HCN is H-C≡N.
- In this molecule, there is a single bond between hydrogen and carbon, and a triple bond between carbon and nitrogen.
- Conclusion: HCN has both a single bond and a triple bond. **Not the answer.**

4. **Analyze N2 (Dinitrogen)**:
- The structure of N2 is N≡N.
- In this molecule, there is a triple bond between the two nitrogen atoms, with each nitrogen atom having one lone pair of electrons.
- Conclusion: N2 has only a triple bond. **This is the answer.**

### Final Answer:
The molecule that contains only a triple bond is **N2 (Dinitrogen)**.

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