An aqueous compound of an inorganic compound `(X)` shows the following reactions:
a. it decolourises and acidified `KMnO_(4)` solution accompanied by the evolution of oxygen.
b. it liberates `I_(2)` from an acidified `KI` solution.
c. It gives a brown precipitate with alkaline `KMnO_(4)` solution with evolution of oxygen.
d. It removes black stains from old oil paintings. Identify `(X)` and give chemical equtions for the reaction at steps (a) to (d).

Explanation

To identify the aqueous compound \( (X) \) and provide the chemical equations for the reactions described, we will analyze each reaction step by step.

### Step 1: Identify the Compound \( (X) \)
The compound \( (X) \) shows the following characteristics:
- It decolorizes acidified \( KMnO_4 \) solution and evolves oxygen.
- It liberates \( I_2 \) from acidified \( KI \) solution.
- It gives a brown precipitate with alkaline \( KMnO_4 \) solution and evolves oxygen.
- It removes black stains from old oil paintings.
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