Answer
Complete ionic equation:
$6Na^+(aq) + 2PO{_4}^{3-}(aq) + 3Ni^{2+}(aq) + 6Cl^-(aq) -- \gt Ni_3(PO_4)_2(s) + 6Na^+(aq) +6Cl^-(aq)$
Net ionic equation:
$2PO{_4}^{3-}(aq) + 3Ni^{2+}(aq) -- \gt Ni_3(PO_4)_2(s)$
Work Step by Step
1. Balance the equation:
$Na_3PO_4(aq) + NiCl_2(aq) -- \gt Ni_3(PO_4)_2(s) + NaCl(aq)$
Balance the number of $P$, by putting a 2 before $Na_3PO_4:$
$2Na_3PO_4(aq) + NiCl_2(aq) -- \gt Ni_3(PO_4)_2(s) + NaCl(aq)$
Balance the number of $Na$, by putting a 6 before $NaCl$:
$2Na_3PO_4(aq) + NiCl_2(aq) -- \gt Ni_3(PO_4)_2(s) + 6NaCl(aq)$
Balance the number of $Ni$ and $Cl$, by putting a 3 before $NiCl$:
$2Na_3PO_4(aq) + 3NiCl_2(aq) -- \gt Ni_3(PO_4)_2(s) + 6NaCl(aq)$
2. For the strong electrolytes in aqueous state, separate the ions:
$Na_3PO_4, NiCl_2$ and $NaCl$: Strong electrolytes. (Completely dissociated in water).
$6Na^+(aq) + 2PO{_4}^{3-}(aq) + 3Ni^{2+}(aq) + 6Cl^-(aq) -- \gt Ni_3(PO_4)_2(s) + 6Na^+(aq) +6Cl^-(aq)$
- This is the balanced complete ionic equation.
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3. Remove the spectator ions:
- Remove the ions that appear unchanged after the reaction.
$6Na^+$ and $6Cl^-$ don't react.
$2PO{_4}^{3-}(aq) + 3Ni^{2+}(aq) -- \gt Ni_3(PO_4)_2(s)$
- This is the balanced net ionic equation.