The value in electron-volt per atom which represent the first ionisation energy of oxygen and nitrogen atom respectively are

Options

A. 41.6,13.6
B. 13.6 , 14.6
C. 13.6 , 13.6
D. 14.6,14.6

Explanation

To find the first ionization energy of oxygen and nitrogen in electron volts per atom, we can follow these steps:

### Step 1: Understand the Electron Configuration
- **Oxygen (O)** has an atomic number of 8, and its electron configuration is \(1s^2 2s^2 2p^4\).
- **Nitrogen (N)** has an atomic number of 7, and its electron configuration is \(1s^2 2s^2 2p^3\).

### Step 2: Identify the Group and Stability
- Oxygen is in Group 16, while nitrogen is in Group 15.
- The \(2p\) subshell of nitrogen has 3 electrons, which means it is half-filled. Half-filled and fully filled subshells are more stable than other configurations.

### Step 3: Analyze Ionization Energy
- Ionization energy is the energy required to remove an electron from an atom.
- Since nitrogen has a half-filled \(2p\) subshell, it is more stable and requires more energy to remove an electron compared to oxygen, which has a less stable configuration.

### Step 4: Compare the Values
- The first ionization energy values are approximately:
- **Nitrogen (N)**: 14.6 eV
- **Oxygen (O)**: 13.6 eV
- Therefore, the ionization energy of nitrogen is greater than that of oxygen.

### Step 5: Conclusion
- The first ionization energies of oxygen and nitrogen in electron volts per atom are 13.6 eV for oxygen and 14.6 eV for nitrogen, respectively.

### Final Answer
- The values in electron-volt per atom representing the first ionization energy of oxygen and nitrogen are:
- Nitrogen: 14.6 eV
- Oxygen: 13.6 eV

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