The chemical formula for cadmium(II) perchlorate is Cd(ClO₄)₂. Here's why:

* Cadmium(II): Cadmium is a transition metal with a +2 charge in this compound (hence the Roman numeral II).

* Perchlorate: The perchlorate ion is ClO₄⁻, with a -1 charge.

* Balancing Charges: To balance the charges, we need two perchlorate ions (2 x -1 = -2) to match the +2 charge of the cadmium ion.

Therefore, the formula is Cd(ClO₄)₂.