Question

Which of the following has maximum value of cation/anion ratio?

• A. KCl
• B. NaCl
• C. $Ca{F}_2$
• D. $MgC{l}_2$

Answer 1

Answer: (C)

Among the three options $KCl,NaCl$ and $MgC{l}_2$, the size of anion is same. So larger the cation, larger will be the cation/anion ratio i.e., $KCl$ will have larger cation/anion ratio among the three. So, we left with two options $KCl$ and $Ca{F}_2$. Among these two $Ca{F}_2$ will have maximum value of cation/anion ratio because decrease in ionic radii of anion from $C{l}^{-}$to $F^{-}$does not overcome the effect of decrease in ionic radii of cation from $K+$ to $C{a}^{2+}$