Write complete chemical equation for :
(i) Oxidation of `Fe^(2+)"by" Cr_(2)O_(7)^(2-)` in acid medium
(ii) Oxidation of `S_(2)O_(3)^(2-) "by" MnO_(4)^(-)` in neutral aqueous medium

Explanation

To solve the given question, we will write the complete chemical equations for both reactions step by step.

### (i) Oxidation of `Fe^(2+)` by `Cr_(2)O_(7)^(2-)` in acid medium

1. **Identify the reactants and products**:
- Reactants: `Fe^(2+)` (ferrous ion) and `Cr_(2)O_(7)^(2-)` (dichromate ion).
- Products: `Fe^(3+)` (ferric ion) and `Cr^(3+)` (chromium ion).

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