Two Types of Ionic Compounds

• Type I (Fixed Charge)
• Metals whose ions can only have one possible charge
• 1A, 2A, (Al, Zn, Ag)
• Determine charge by position on the periodic table
• 1A = +; 2A = 2+; Al, Ga, In = 3+
• Some need to be memorized
• Zn = 2+, Cd = 2+, Ag = +
• Type II (Variable Charge)
• Metals whose ions can have more than one possible charge (everything else!)
• Determine charge by the charge on anion

How do you know a metal cation is Type II?