Question

a polyatomic ion is named hydroxide. what is the formula of this ion?

Explanation:

Step1: Recall polyatomic ion formula

Hydroxide is a common polyatomic ion. Its formula is known to be $\ce{OH^-}$. The hydroxide ion consists of one oxygen atom and one hydrogen atom, with a -1 charge.

Answer:

The formula of the hydroxide ion is $\boldsymbol{\ce{OH^-}}$.