`E^(-)` of some elements are given as `:`
`{:(I_(2)+2e^(-)rarr 2I^(-),,,,E^(-)=0.54V),(MnO_(4)^(-)+8H^(o+)+5e^(-)rarr Mn^(2+)+4H_(2)O,,,,E^(-)=1.52V),(Fe^(3+)+e^(-)rarr Fe^(2+),,,,E^(-)=0.77V),(Sn^(4+)+2e^(-)rarr Sn^(2+),,,,E^(-)=0.1V):}`
`a.` Select the stronges reductant and weakes oxidant among these elements.
`b.` Select the weakest reductant and strongest oxidant among these elements.

Options

A. `Zn`
B. `Cr`
C. `H_(2)`
D. `Fe`

Explanation

To solve the question, we need to analyze the standard reduction potentials (E°) provided for each half-reaction and determine the strongest and weakest reductants and oxidants based on these values.

### Given Standard Reduction Potentials:
1. \( I_2 + 2e^- \rightarrow 2I^- \), \( E° = 0.54 \, V \)
2. \( MnO_4^- + 8H^+ + 5e^- \rightarrow Mn^{2+} + 4H_2O \), \( E° = 1.52 \, V \)
3. \( Fe^{3+} + e^- \rightarrow Fe^{2+} \), \( E° = 0.77 \, V \)
4. \( Sn^{4+} + 2e^- \rightarrow Sn^{2+} \), \( E° = 0.10 \, V \)

### Step-by-Step Solution:

#### Part (a): Strongest Reductant and Weakest Oxidant
1. **Identify the strongest reductant**:
- The strongest reductant corresponds to the species with the lowest standard reduction potential (E°), as it is more likely to lose electrons (be oxidized).
- Among the given values, \( Sn^{4+} + 2e^- \rightarrow Sn^{2+} \) has the lowest E° of \( 0.10 \, V \).
- Therefore, the strongest reductant is **\( Sn^{4+} \)**.

2. **Identify the weakest oxidant**:
- The weakest oxidant corresponds to the species with the highest standard reduction potential (E°), as it is less likely to gain electrons (be reduced).
- The highest E° is \( MnO_4^- + 8H^+ + 5e^- \rightarrow Mn^{2+} + 4H_2O \) with \( E° = 1.52 \, V \).
- Therefore, the weakest oxidant is **\( MnO_4^- \)**.

#### Part (b): Weakest Reductant and Strongest Oxidant
1. **Identify the weakest reductant**:
- The weakest reductant corresponds to the species with the highest standard reduction potential (E°), as it is less likely to lose electrons (be oxidized).
- As established, the highest E° is \( MnO_4^- \) with \( E° = 1.52 \, V \).
- Therefore, the weakest reductant is **\( MnO_4^- \)**.

2. **Identify the strongest oxidant**:
- The strongest oxidant corresponds to the species with the lowest standard reduction potential (E°), as it is more likely to gain electrons (be reduced).
- The lowest E° is \( Sn^{4+} \) with \( E° = 0.10 \, V \).
- Therefore, the strongest oxidant is **\( Sn^{4+} \)**.

### Summary of Answers:
- **Strongest Reductant**: \( Sn^{4+} \)
- **Weakest Oxidant**: \( MnO_4^- \)
- **Weakest Reductant**: \( MnO_4^- \)
- **Strongest Oxidant**: \( Sn^{4+} \)