Activated charcoal is used to remove colouring matter from pure substance, it works by

Options

A. Oxidation
B. Reduction
C. Bleaching
D. Adsorption

Explanation

**Step-by-Step Solution:**

1. **Understanding Activated Charcoal**: Activated charcoal is a form of carbon that has been processed to have a vast surface area. This high surface area allows it to adsorb various substances, including coloring agents.

2. **Defining Adsorption**: Adsorption is a surface phenomenon where molecules adhere to the surface of a solid or liquid. This is different from absorption, where a substance permeates or is taken up by the bulk of another substance.

3. **Mechanism of Action**: When activated charcoal is introduced to a solution containing coloring matter, the molecules of the coloring agents are attracted to and adhere to the surface of the activated charcoal. This process effectively removes the coloring matter from the solution.

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