can you tell me how you got the answer? i get confused on the ratios, help?
Because Ca has a charge of 2+ and S has a charge of 2-, so if you cross multiply those charges you get Ca2S2, which can simplify to CaS, a 1:1 ratio.
...S does not have a charge of 3-
none of the above.
ionic charge of Ca is +2, S is -3
you might be missing information