Need help with this

Question

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

PO4^3-, Fe^3+, Pb^4+, CN^−

Answer 1

Haven't you figured out how to do this yet. You've posted similar questions and received proper answers, so one would hope that you've learned how to do this by now. Here are two of the four answers. Maybe you can determine the other two.

Fe³⁺ and PO₄^3- ==> FePO₄ (you have a 3+ and a 3- canceling each other)

Fe³⁺ and CN^- = Fe(CN)₃ (you have a 3+ and so need 3 of the 1- to cancel, so use 3 CN^-)