The reducing nature of any metal in aqueous solution depends upon
a.Enthalpy of atomisation
b. Ionisation enthalpies
c. Hydration energy

Options

A. a & b only
B. Only b
C. b&c only
D. a, b &C

Answer

To determine the reducing nature of any metal in aqueous solution, we need to analyze the three factors mentioned: enthalpy of atomization, ionization enthalpy, and hydration energy.

### Step-by-Step Solution:

1. **Understanding Reducing Agents**:
- A reducing agent is a substance that loses electrons and, in doing so, reduces another substance. Metals typically act as reducing agents because they can easily lose electrons.

2. **Enthalpy of Atomization**:
- This is the energy required to convert one mole of a solid metal into gaseous atoms. It is an endothermic process, meaning it requires energy input. A lower enthalpy of atomization indicates that the metal can more easily form gaseous atoms, which is favorable for reducing behavior.

3. **Ionization Enthalpy**:
- This is the energy required to remove an electron from a gaseous atom to form a cation. This process is also endothermic. Metals with low ionization enthalpy can lose electrons more easily, which enhances their ability to act as reducing agents.

4. **Hydration Energy**:
- When metal ions are dissolved in water, they become surrounded by water molecules, a process that releases energy (exothermic). High hydration energy means that when the metal ion is formed, it is stabilized by the surrounding water molecules. This stabilization is crucial for the metal to effectively act as a reducing agent in solution.

5. **Conclusion**:
- For a metal to be a strong reducing agent, it should have:
- Low enthalpy of atomization (to easily form gaseous atoms),
- Low ionization energy (to easily lose electrons),
- High hydration energy (to stabilize the resulting cation in solution).
- Therefore, the reducing nature of any metal in aqueous solution depends on all three factors: enthalpy of atomization, ionization enthalpy, and hydration energy.

### Final Answer:
The reducing nature of any metal in aqueous solution depends upon:
- **a. Enthalpy of atomization**
- **b. Ionization enthalpies**
- **c. Hydration energy**

Thus, all three factors are important.

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