Question

When a solution of magnesium nitrate is mixed with a solution of sodium phosphate, the solid that forms is magnesium phosphate. Select the equation that represents the complete ionic equation. A. Mg(NO3)2(aq) + Na2PO4(aq)  MgPO4(s) + NaNO3(aq) B. Mg2+(aq) + PO43-(aq)  MgPO4(s) C. 3Mg(NO3)2(aq) + 2Na3PO4(aq)  Mg3(PO4)2(s) + 6NaNO3(aq) D. 3Mg2+(aq) + 2PO43-(aq)  Mg3(PO4)2(s) E. 3Mg2+(aq)+6NO3-(aq) + 6Na+(aq) + 2PO43-(aq) Mg3(PO4)2(s)+6NO3-(aq)+ 6Na+(aq)

Answer 1

Answer : The correct option is, (E)

`3Mg^(2+)(aq)+6NO_3^(-)(aq)+6Na^+(aq)+2PO_4^(3-)(aq)\rightarrow 6Na^+(aq)+6NO^(3-)(aq)+Mg_3(PO_4)_2(s)`

Explanation :

Complete ionic equation : In complete ionic equation, all the substance that are strong electrolyte and present in an aqueous are represented in the form of ions.

Net ionic equation : In the net ionic equations, we are not include the spectator ions in the equations.

Spectator ions : The ions present on reactant and product side which do not participate in a reactions. The same ions present on both the sides.

The balanced molecular equation will be,

`3Mg(NO_3)_2(aq)+2Na_3PO_4(aq)\rightarrow 6NaNO_3(aq)+Mg_3(PO_4)_2(s)`

The complete ionic equation in separated aqueous solution will be,

`3Mg^(2+)(aq)+6NO_3^(-)(aq)+6Na^+(aq)+2PO_4^(3-)(aq)\rightarrow 6Na^+(aq)+6NO^(3-)(aq)+Mg_3(PO_4)_2(s)`