Answer
The chemical formula for ammonium hydroxide is $NH_4OH$
Work Step by Step
** Since the last name is "hydroxide", we can assume that it will act as a base in water.
"Ammonium" is the name of the polyatomic ion: $NH_4^+$, which has a charge equal to $1+.$
"Hydroxide" represents the ion formed by a hydrogen and an oxygen atom, with a single negative charge: $OH^-$. (Hydroxide ion)
Since the charges are already balanced ("+1" and "-1"), we can simply put these 2 ions together:
$NH_4OH$
