Hydride of certain non - metallic element X is amphoteric in nature. It also reacts with sodium hydride as well with metallic sodium to liberate dihydrogen gas. The element X can be

Options

A. Nitrogen
B. Carbon
C. Oxygen
D. Sulphur

Answer

To solve the problem, we need to identify the non-metallic element X whose hydride is amphoteric in nature and reacts with both sodium hydride and metallic sodium to liberate dihydrogen gas.

### Step-by-Step Solution:

1. **Understanding Amphoteric Nature**:
- Amphoteric substances can react with both acids and bases. This means that the hydride of element X must be able to donate protons (acting as an acid) and accept protons (acting as a base).

2. **Analyzing the Options**:
- We will evaluate each option to see if it meets the criteria of being amphoteric and capable of reacting with sodium hydride and metallic sodium.

3. **Option 1: Nitrogen (N)**:
- The common hydrides of nitrogen include NH3 (ammonia), N2H4 (hydrazine), and N2H2 (hydrazine).
- NH3 is basic and does not exhibit amphoteric behavior. Therefore, nitrogen is not the correct answer.

4. **Option 2: Carbon (C)**:
- The hydrides of carbon, such as CH4 (methane), do not show amphoteric properties. They are stable and do not have lone pairs to donate or accept protons. Thus, carbon is also not the correct answer.

5. **Option 3: Oxygen (O)**:
- The hydride of oxygen is H2O (water), which is known to be amphoteric.
- Water can react with acids (e.g., HCl) to form H3O+ and with bases (e.g., NaOH) to form OH-.
- Additionally, water can react with sodium hydride (NaH) and metallic sodium (Na) to liberate dihydrogen gas (H2).
- Reaction with NaH:
\[ H2O + NaH \rightarrow NaOH + H2 \]
- Reaction with metallic sodium:
\[ 2H2O + 2Na \rightarrow 2NaOH + H2 \]
- Therefore, oxygen is a valid candidate for element X.

6. **Option 4: Sulfur (S)**:
- The hydride of sulfur is H2S (hydrogen sulfide), which is not amphoteric. It does not react with bases to form salts. Therefore, sulfur is also not the correct answer.

7. **Conclusion**:
- The only element that fits all the criteria is oxygen (O).

### Final Answer:
The element X can be **Oxygen**.