* +1: This is the most common charge for hydrogen. It loses one electron to form a positively charged ion, H+. This is the form of hydrogen you'll most often encounter in acids and other compounds.
* -1: This is less common but possible. Hydrogen can gain one electron to form a negatively charged ion, H-. This is called a hydride ion, and it's found in some metal hydrides.
So, the specific ionic charge of hydrogen depends on the context of the compound it's in.
