$1\, L \,of\, X + Excess\, of\, AgNO_3 \rightarrow Y\, mol\, of\, ppt.$
$1\, L\, of\, X + Excess\, of\, BaCl_2 \rightarrow Z\, mol\, of\, ppt.$
તો $Y$ અને $Z$ અનુક્રમે ............... થશે.
$(A)$ $\left[ Ni \left( H _{2} O \right)_{2}( en )_{2}\right]^{2+}$
$(B)$ $\left[ Ni \left( H _{2} O \right)_{4}(\text { en })\right]^{2+}$ અને
$(C)$ $\left[ Ni ( en )_{3}\right]^{2+}$