Which has the most stable `+2` oxidation state ?

Options

A. `Sn`
B. `Fe`
C. `Pb`
D. `Ag`

Explanation

To determine which element has the most stable +2 oxidation state among the given options, we will analyze the oxidation states of each element based on their group in the periodic table and the effects that influence their stability.

### Step-by-Step Solution:

1. **Identify the Elements**: The elements mentioned are tin (Sn), lead (Pb), iron (Fe), and silver (Ag).

2. **Group Classification**:
- Tin (Sn) and Lead (Pb) belong to Group 14 of the periodic table.
- Iron (Fe) is a transition metal in the d-block.
- Silver (Ag) is also a transition metal.

3. **Oxidation States**:
- **Iron (Fe)**: The +2 oxidation state (Fe²⁺) is common, but it can also exist in the +3 oxidation state (Fe³⁺). The stability of these states depends on the electron configuration. Fe²⁺ has the configuration of 3d⁶, which is less stable compared to fully filled or half-filled configurations.
- **Silver (Ag)**: The +1 oxidation state (Ag⁺) is more stable than the +2 oxidation state (Ag²⁺). Silver tends to lose only one electron to achieve a stable configuration.
- **Tin (Sn)**: In Group 14, Sn can exhibit +2 and +4 oxidation states. However, the +2 state is less stable compared to lead.
- **Lead (Pb)**: As we move down Group 14, the +2 oxidation state becomes more stable due to the inert pair effect. Lead (Pb) has a +2 oxidation state that is more stable than that of tin.

4. **Inert Pair Effect**: This effect refers to the tendency of the outermost s-electrons to remain non-bonding in heavier elements. For lead, this means that the +2 oxidation state is favored over the +4 state.

5. **Conclusion**: Among the given elements, lead (Pb) has the most stable +2 oxidation state due to its position in the periodic table and the inert pair effect.

### Final Answer:
Lead (Pb) has the most stable +2 oxidation state.

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