Answer
$NH{_4}^+ + H_2O \rightleftharpoons NH_3 + H_3O^+$
Work Step by Step
1. Identify the reactants.
Ammonium ion and water: $NH{_4}^+$ and $H_2O$
2. Find the products.
- As the exercise says, $NH{_4}^+$ will donate an $H^+$ to $H_2O$. Thus, we just need to find the conjugate base for the ammonium ion and the conjugate acid for water.
$NH{_4}^+ \longrightarrow NH_3$
$H_2O \longrightarrow H_3O^+$
3. Write the equation.
$NH{_4}^+ + H_2O \rightleftharpoons NH_3 + H_3O^+$
