Step-by-step explanation:
for a transition metal you can determine the charge by the number after it e.g chromium(ii) In this case it has a charge of 2+ but for metals and non metals its charge is determined by the group it is in for
e.g hydrogen; we are meant to find its charge, it is on the group1 of the periodic table and so has a charge of +1. anyways do you mean within a compound like hydrogen peroxide or silver chloride ?