\({N_1}{V_1} = {N_2}{V_2}\); \(25 \times {N_1} = 0.1 \times 35\)
\({N_1} = \frac{{0.1 \times 35}}{{25}}\) ;
\(\therefore M = \frac{{0.1 \times 35}}{{25 \times 2}} = 0.07\).
$(i)$ $0.10\, {M} \,{Ba}_{3}\left({PO}_{4}\right)_{2}$
$(ii)$ $0.10\, {M}\, {Na}_{2} {SO}_{4}$
$(iii)$ $0.10\, {M}\, {KCl}$
$(iv)$ $0.10 \,{M} \,{Li}_{3} {PO}_{4}$