K₃PO₄(aq) reacts with Al(NO₃)₃(aq) and form AlPO₄(s) and KNO₃(aq) as the products.
Before writing net ionic reaction, following steps should be followed.
Step 1 : Write the balanced chemical equation for the reaction and indicate the state of compound as aq,s,g or l.
K₃PO₄(aq) + Al(NO₃)₃(aq) → AlPO₄(s) + 3KNO₃(aq)
Step 2 : Identify the ionic species which dissolve in water to form ions.
K₃PO₄(aq) → 3K⁺(aq) + PO₄⁻(aq)
Al(NO₃)₃(aq) → Al³⁺(aq) + 3NO₃⁻(aq)
KNO₃(aq) → K⁺(aq) + NO₃⁻(aq)
Step 3 : Write the equation again by using ions.
3K⁺(aq) + PO₄⁻(aq) + Al³⁺(aq) + 3NO₃⁻(aq) → AlPO₄(s) +3K⁺(aq) + 3NO₃⁻(aq)
Step 4 : Identify the similar species in both side of the equation and cut off them.
3K⁺(aq) and 3NO₃⁻(aq) present in both sides. Hence, those ions can be cut off.
Step 5 : Get the final ionic equation.
The net ionic equation for the given reaction is
Al³⁺(aq) + PO₄⁻(aq) → AlPO₄(s)