The most stable +2 oxidation state is exhibited by

Options

A. Ge
B. Sn
C. Pb
D. Si

Explanation

To determine which element exhibits the most stable +2 oxidation state among Ge (Germanium), Sn (Tin), Pb (Lead), and Si (Silicon), we can follow these steps:

### Step 1: Understand the Group and Oxidation States
The elements listed belong to Group 14 of the periodic table, also known as the carbon family. In this group, elements can exhibit multiple oxidation states, primarily +4 and +2.

### Step 2: Analyze the Trend in Stability of Oxidation States
As we move down the group from Si to Pb, the stability of the +2 oxidation state increases while the stability of the +4 oxidation state decreases. This trend is primarily due to the inert pair effect.

### Step 3: Explain the Inert Pair Effect
The inert pair effect refers to the phenomenon where the two electrons in the outermost s orbital (ns²) become less available for bonding as we move down the group. This is because the increasing atomic size leads to a greater distance from the nucleus, and the shielding effect from inner d and f electrons reduces the effective nuclear charge felt by the outer s electrons.

### Step 4: Identify the Most Stable +2 Oxidation State
- **Si (Silicon)**: Exhibits +4 oxidation state more readily than +2.
- **Ge (Germanium)**: Can exhibit both +2 and +4, but +4 is more stable.
- **Sn (Tin)**: Exhibits both +2 and +4; however, +2 is becoming more stable.
- **Pb (Lead)**: Exhibits +2 oxidation state more stably than +4 due to the inert pair effect.

### Conclusion
Among the elements listed, **Pb (Lead)** exhibits the most stable +2 oxidation state due to the inert pair effect, which makes the +4 state less favorable.

### Final Answer
The most stable +2 oxidation state is exhibited by **Pb (Lead)**.

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