Which pair of elements can form multiple bond with itself and oxygen ?

Options

A. F,N
B. N, Cl
C. N,P
D. N,C

Answer

To determine which pair of elements can form multiple bonds with themselves and with oxygen, we need to analyze the bonding capabilities of the elements in the given options. Here’s a step-by-step solution:

### Step 1: Understand the concept of multiple bonds
Multiple bonds refer to double or triple bonds between atoms. For an element to form multiple bonds with itself or with oxygen, it must have the ability to share more than one pair of electrons.

### Step 2: Analyze each option
We will evaluate each pair of elements provided in the options.

#### Option A: Fluorine and Nitrogen
- **Fluorine (F)**: Electronic configuration is 1s² 2s² 2p⁵. It cannot expand its octet due to the absence of d-orbitals and has high electronegativity, which prevents it from forming multiple bonds.
- **Nitrogen (N)**: Electronic configuration is 1s² 2s² 2p³. Nitrogen can form a triple bond with itself (N≡N) and can also form multiple bonds with oxygen (e.g., NO, N₂O₃).

**Conclusion**: Fluorine cannot form multiple bonds, so this option is incorrect.

#### Option B: Nitrogen and Chlorine
- **Chlorine (Cl)**: Chlorine can form single bonds easily but does not have the ability to form multiple bonds with itself due to its larger atomic size. It can form some multiple bonds with oxygen (e.g., ClO₂), but not with itself.
- **Nitrogen (N)**: As previously established, nitrogen can form multiple bonds.

**Conclusion**: Chlorine cannot form multiple bonds with itself, so this option is incorrect.

#### Option C: Nitrogen and Phosphorus
- **Phosphorus (P)**: While phosphorus can form single bonds with itself (P₄) and can form multiple bonds with oxygen (e.g., PCl₅), it does not form multiple bonds with itself due to its larger atomic size compared to nitrogen.
- **Nitrogen (N)**: Again, nitrogen can form multiple bonds.

**Conclusion**: Phosphorus cannot form multiple bonds with itself, so this option is incorrect.

#### Option D: Nitrogen and Carbon
- **Carbon (C)**: Carbon can form multiple bonds with itself (e.g., C≡C in alkynes) and with oxygen (e.g., CO₂).
- **Nitrogen (N)**: As previously established, nitrogen can also form multiple bonds.

**Conclusion**: Both nitrogen and carbon can form multiple bonds with themselves and with oxygen, making this option correct.

### Final Answer
The pair of elements that can form multiple bonds with themselves and with oxygen is **Nitrogen and Carbon**.

---