Question

In the chemical reaction of aluminium and copper chloride ( Al + CuCl2 = AlCl3 + Cu). Why dont we write the valency of aluminium and copper individually? And why do we write them only when they react with chloride?

Answer 1

Answer:

Explanation:

This is called criss-cross method by which we criss cross them by using their valencies. When there might be difference in reactants and products because

if we criss cross the valencies or charges may change.