2 g of ferrous sulphate crystals are heated in a dry boiling tube.
List any two observations.

Explanation

**Step-by-Step Solution:**

1. **Initial Observation**: When 2 g of ferrous sulphate (FeSO4) crystals are placed in a dry boiling tube, the initial color of the crystals is green. This is a characteristic property of ferrous sulphate.

2. **Heating Process**: As the ferrous sulphate is heated in the boiling tube, the temperature increases, and the crystals begin to undergo a thermal decomposition reaction.

3. **Color Change**: During the heating process, the green ferrous sulphate crystals change color. This change is observed as the crystals turn into a brown solid. This brown solid is anhydrous ferrous sulphate, which is formed after the loss of water molecules from the hydrated ferrous sulphate.

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