* Cadmium's Electron Configuration: Cadmium (Cd) has an atomic number of 48, so its electron configuration is [Kr] 4d¹⁰ 5s².
* Pseudo Noble Gas Configuration: A pseudo noble gas configuration refers to an ion having the same electron configuration as the previous noble gas. The previous noble gas for cadmium is krypton (Kr), which has the configuration [Kr].
* Achieving the Configuration: To achieve the [Kr] configuration, cadmium needs to lose its two outer electrons (5s²).
* Ion Formation: Losing two electrons results in a +2 charge.
Therefore, the formula of the ion formed when cadmium achieves a pseudo noble gas electron configuration is Cd²⁺.
