The correct option is D Molarities of Na+ and NO−3 ions are 0.6 and 1.0 respectively
The corresponding balanced reaction is:
2Na3PO4(aq)+3Ba(NO3)2(aq)→Ba3(PO4)2(aq)↓+6NaNO3(aq)
So, Na3PO4 is the limiting reagent and is completely consumed.
Moles of Ba3(PO4)2 formed =0.22 mol=0.1 mol
Moles of unreacted Ba(NO3)2=(0.5−0.3) mol=0.2=mol of Ba2+ ion.
The reacted 0.3 mol Ba2+ will be precipitated as 0.1 mol barium phosphate.
Moles of Na+ in solution =0.2×3=0.6
Moles of NO−3 in solution =0.5×2=1