Question

Using general solubility rules, write the balanced molecular equation when the following aq solutions are mixed. Underline the formula of the solid. If no precipitation reaction is likely, explain why.
A. NHY4Cl, H2SO4
B. K2CO3, SnCl4
C. NH4Cl, Pb(NO3)2
D. CuSO4, KOH
E.Na3PO4, CrCl3
F. (NH4)2S, FeCl3

Answer 1

You need to know the solubility rules. Here is a simple set of rules that will cover most (not all) salts.
http://www.chem.vt.edu/RVGS/ACT/notes/solubility_rules.html

For example, NH4Cl + H2SO4.
the possible combinations, if you look at a double replacement reaction, is HCl + NH4SO4. By the rules, ammonium salts are soluble so there is no ppt.