Write the compounds of aluminiium with the following elements.
Oxygen, Sulphur, Nitrogen.

Explanation

To write the compounds of aluminum with oxygen, sulfur, and nitrogen, we need to consider the valency of aluminum and the other elements. Here’s a step-by-step solution:

### Step 1: Identify the Valency of Aluminum
Aluminum (Al) has an atomic number of 13 and its electronic configuration is 2, 8, 3. This means it has 3 electrons in its outermost shell, which it can lose to achieve a stable configuration. Therefore, the valency of aluminum is +3.

### Step 2: Identify the Valency of Oxygen
Oxygen (O) has an atomic number of 8 and its electronic configuration is 2, 6. It needs 2 more electrons to complete its outer shell, so the valency of oxygen is -2.

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