Write the formula of the sulphate of the element with atomic number 13.

Explanation

To find the formula of the sulfate of the element with atomic number 13, follow these steps:

### Step 1: Identify the Element
The element with atomic number 13 is Aluminum (Al).

### Step 2: Determine the Valency of Aluminum
Aluminum has an electronic configuration of 1s² 2s² 2p⁶ 3s² 3p¹. From this configuration, we can see that Aluminum has 3 valence electrons. Therefore, the valency of Aluminum is +3.

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