What is tincture of iodine ? What is its use ?

Explanation

### Step-by-Step Solution:

1. **Definition of Tincture of Iodine**:
- Tincture of iodine is a dilute solution of elemental iodine, typically combined with sodium iodide (NaI) or potassium iodide (KI) in a mixture of water and alcohol (ethanol). It is also known as iodine tincture.

2. **Composition**:
- The tincture usually contains about 2-7% of elemental iodine, with the remaining components being sodium iodide or potassium iodide dissolved in a solvent of water and ethanol.

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