what is the net ionic charge of a calcium ion?
What is the charge on the strontium ion? and what is the net charge of the ionic compound calcium fluoride?? For a compound, you need to detemine the charge of each ions first. For calcium, it is in Group 2, so the charge is 2+. Fluorine is in Group 7, but the charge is not 7+. It is in different case because fluorine is a non-metallic ion - it is a halogen (refer to the periodic table). So in order to predict the charge of halogens, simply take 8 and minus with the Group number.