What is the charge of a hydroxide ion?

The charge of a hydroxide ion is indeed 1-. A hydroxide ion consists of one oxygen atom covalently bonded to one hydrogen atom (OH). In this ion, the oxygen atom carries a charge of -2 due to its electronegativity, while hydrogen normally has a charge of 0. However, since the hydroxide ion has gained an extra electron (making it negatively charged), the overall charge of the hydroxide ion is -1. Therefore, it is correct to state that a hydroxide ion has a charge of 1-. This understanding of the structure and electron configuration of the hydroxide ion is crucial for grasping its role in various chemical reactions and compounds.