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Question

Write the empirical formula for at least four ionic compounds that could be formed from the following ions

Fe^3+, PO4^3-, Fe^2+, ClO3^-

Answer 1

To form an ionic bond to produce a formula of an ionic compound the (+) charges must balance out the (-) charges to equal 0. You determine the number of ions of each cation (+) charged ions and each anion (-) charged ions that will add to zero forming the compound.

1) FePO4 1 ion of Fe^3+ ionically bonds with 1 polyatomic ion PO4-3, the charges adding to zero

2) Fe(ClO3)3 1 Ion of Fe^3+ ionically bonds with 3 polyatomic ions of ClO3-1 - charges add to zero

3) Fe3(PO4)2 3 ions of Fe^2+ ionically bonds with 2 polyatomic ions of PO4-3 - charges add to zero

4) Fe(ClO3)2 1 ion Fe^2+ ionically bonds with 2 polyatomic ions of ClO3- - charges add to zero