The first ionisation potential in electron volts of nitrogen and oxygen atoms are respectively given by

Options

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

Explanation

To find the first ionization potential in electron volts of nitrogen and oxygen atoms, we can follow these steps:

### Step 1: Understand Ionization Potential
Ionization potential (or ionization energy) is the amount of energy required to remove one electron from a neutral isolated gaseous atom.

### Step 2: Determine the Electronic Configurations
- **Nitrogen (N)** has an atomic number of 7. Its electronic configuration is:
\[ 1s^2 \, 2s^2 \, 2p^3 \]
- **Oxygen (O)** has an atomic number of 8. Its electronic configuration is:
\[ 1s^2 \, 2s^2 \, 2p^4 \]

### Step 3: Analyze the Stability of the Orbitals
- For **Oxygen** (2p4), if we remove one electron, it will become:
\[ 1s^2 \, 2s^2 \, 2p^3 \]
This configuration is half-filled, which is more stable. Therefore, it is easier to remove an electron from oxygen, resulting in a lower ionization potential.

- For **Nitrogen** (2p3), if we remove one electron, it will become:
\[ 1s^2 \, 2s^2 \, 2p^2 \]
This configuration is no longer half-filled, making it more difficult to remove an electron. Thus, nitrogen has a higher ionization potential.

### Step 4: Compare Ionization Potentials
From the analysis:
- The ionization potential of **Oxygen** is lower than that of **Nitrogen**. Therefore, we can conclude that:
\[ \text{Ionization potential of Nitrogen} > \text{Ionization potential of Oxygen} \]

### Step 5: Identify the Correct Answer from Options
Now, we need to check the provided options for the ionization potentials:
1. **Option 1**: 14.6 eV for Nitrogen and 13.6 eV for Oxygen.
2. **Option 2**: (other values)
3. **Option 3**: (other values)
4. **Option 4**: (other values)

From the analysis, since 14.6 eV (Nitrogen) is greater than 13.6 eV (Oxygen), **Option 1** is the correct answer.

### Final Answer
The first ionization potential in electron volts of nitrogen and oxygen atoms are respectively given by **14.6 eV for Nitrogen and 13.6 eV for Oxygen**.

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