Equimolar solutions of the following were prepared in water separately. Which one of the solutions will…

Equimolar solutions of the following were prepared in water separately. Which one of the solutions will record the highest $\mathrm{pH}$ ?
  1. $\mathrm{SrCl}_2$
  2. $\mathrm{BaCl}_2$
  3. $\mathrm{MgCl}_2$
  4. $\mathrm{CaCl}_2$

Solution

Key Idea : As the basic nature increases, $p H$ increases
$\text {pH of base } > 7$
$p H$ of acid $ < 7$
In alkaline earth metals on moving downward the size of cation increases, thus basicity increases. Hence, the increasing order of basicity is as :
$\mathrm{MgCl}_2 < \mathrm{CaCl}_2 < \mathrm{SnCl}_2 < \mathrm{BaCl}_2$
Therefore, the solution of $\mathrm{BaCl}_2$ will record the highest $\mathrm{pH}$.

Asked in: NEET 2008 (Screening)

Practice more Ionic Equilibria questions on Aicharya