The chemical behaviour and relative inertness of hydrogen at room temperature depends upon

Options

A. H-H bonding dissociation enthalpy
B. ionisation enthalpy
C. enthalpy of fusion
D. enthalpy of evaporation

Answer

To answer the question regarding the chemical behavior and relative inertness of hydrogen at room temperature, we can break it down step by step.

### Step-by-Step Solution:

1. **Understanding Chemical Behavior**:
- The chemical behavior of hydrogen refers to how it interacts with other elements and compounds. Hydrogen can form bonds with various elements, but its reactivity can vary under different conditions.

2. **Relative Inertness at Room Temperature**:
- Hydrogen is relatively inert at room temperature, meaning it does not readily react with many substances. This inertness is primarily due to the strength of the H-H bond in molecular hydrogen (H₂), which is quite strong.

3. **Bond Energy Consideration**:
- The bond energy of the H-H bond is approximately 436 kJ/mol. This means that a significant amount of energy is required to break this bond and allow hydrogen to react with other substances.

4. **Temperature Influence**:
- At room temperature (around 25°C or 298 K), the thermal energy available is not sufficient to overcome the bond energy of H₂. Therefore, hydrogen remains relatively inert.

5. **High Temperature Requirement for Reactivity**:
- To initiate reactions involving hydrogen, such as combustion or reactions with halogens, higher temperatures (around 5000 K) are often required to provide the necessary energy to break the H-H bond.

6. **Conclusion**:
- The chemical behavior and relative inertness of hydrogen at room temperature depend on the strength of the H-H bond and the insufficient thermal energy available at room temperature to break this bond.

### Final Answer:
The chemical behavior and relative inertness of hydrogen at room temperature depend upon the strength of the H-H bond and the insufficient thermal energy available at room temperature to break this bond.