Answer:
To find the identity of ion X, we need to determine its charge based on the number of electrons it contains. Since ion X combines with two chloride ions (Cl⁻) to form the compound XCl₂, it must have a charge of +2 to balance the charge of the two chloride ions.
Given that ion X contains 20 electrons, we can deduce its charge by subtracting the number of electrons from the neutral atom's total number of electrons. Most transition metals lose their valence electrons to form positive ions.
So, 20 electrons implies the ion X has lost 2 electrons, making it a 2+ cation. The only option that fits this description is option c. Cr²⁺.
