The chemical formula for Barium perbromate is Ba(BrO₄)₂. Here's how we arrive at this formula:

* Barium (Ba) is an alkaline earth metal with a +2 charge.

* Perbromate (BrO₄⁻) is a polyatomic ion with a -1 charge.

To balance the charges, we need two perbromate ions (2 x -1 = -2) to neutralize the +2 charge of barium. This gives us the formula Ba(BrO₄)₂.