To determine the ionic charge of the metal cation in the compound Sn(OH)₂, we start by examining the hydroxide ion (OH–).
Each hydroxide ion carries a charge of -1. Since there are two hydroxide ions in the formula, they collectively contribute a charge of -2 to the compound.
For the compound to remain neutral overall, the charge of the tin (Sn) cation must counterbalance the total negative charge from the two hydroxide ions. Therefore, the charge on the tin cation must be +2 to balance out the -2 charge from the two hydroxide ions.
Hence, the ionic charge of the metal cation (tin, Sn) in Sn(OH)₂ is +2.