Which of the following is the most stable

Options

A. `Pb^(2+)`
B. `Ge^(2+)`
C. `Si^(2+)`
D. `Sn^(2+)`

Explanation

To determine which of the given oxidation states is the most stable among Pd²⁺, Ge²⁺, Si²⁺, and Sn²⁺, we can follow these steps:

### Step 1: Identify the Group
The elements in the question belong to Group 14 of the periodic table, which includes carbon (C), silicon (Si), germanium (Ge), tin (Sn), and lead (Pb).

### Step 2: Understand Oxidation States
In Group 14, elements can exhibit two common oxidation states: +2 and +4. The stability of these oxidation states varies among the elements.

### Step 3: Analyze the Stability Trend
As we move down the group from silicon to lead, the stability of the +2 oxidation state increases due to the inert pair effect. The inert pair effect refers to the tendency of the s-electrons (the ns² electrons) to remain non-bonding and not participate in bonding, making the +2 oxidation state more stable compared to the +4 oxidation state.

### Step 4: Compare the Given Options
- **Pd²⁺**: Palladium is not in Group 14, and its stability in the +2 state is not directly comparable to the Group 14 elements.
- **Ge²⁺**: Germanium is in Group 14, and the +2 state is stable but not the most stable.
- **Si²⁺**: Silicon is also in Group 14, but the +2 state is less stable than that of germanium and tin.
- **Sn²⁺**: Tin is in Group 14, and its +2 oxidation state is more stable than that of silicon and germanium due to the inert pair effect.

### Step 5: Conclusion
Among the given options, **Sn²⁺ (Tin in +2 oxidation state)** is the most stable due to the inert pair effect, which increases the stability of the +2 oxidation state as we go down the group.

### Final Answer
**Sn²⁺ is the most stable among the given options.**

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