Name an ore of aluminium and write its formula.

Explanation

To answer the question, "Name an ore of aluminium and write its formula," we can follow these steps:

### Step 1: Identify an Ore of Aluminium
The first step is to identify a commonly known ore of aluminium. One of the most well-known ores is **bauxite**.

### Step 2: Write the Formula of Bauxite
The chemical formula for bauxite is **Al₂O₃·2H₂O**. This indicates that it is a hydrated form of aluminium oxide.

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