Question

how do I know the charges of an ionic compound?

Answer 1

Ionic charge comes into play when one is dealing with the ionic compounds.

Now to find the ionic charge of an element one has to meke use of the periodic table.

In the periodic table metals are placed on the left and are positive, whereas non-metals are placed on the right and are negative.

Below is the table to show a general trend of charge on the elements on the basis of group they belong to in the periodic table.Note that the trend is generally true, however there are exceptions to the above trend.

The elements that are filled with solid purple color have varying charges or the ionic charge is not appropriate. For these elements charge should be decided on a case by case basis. The rest of the elements are having the charges as indicated at the top of each group.