Q60 / 200 · NEET 2008 (Screening) · Chemistry
Equimolar solutions of the following were prepared in water separately. Which one of the solutions will record the highest $\mathrm{pH}$ ?
- A$\mathrm{SrCl}_2$
- Correct answerB$\mathrm{BaCl}_2$
- C$\mathrm{MgCl}_2$
- D$\mathrm{CaCl}_2$
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 $\mathrm{pH}$.
Hence, the correct answer is option: 'B'.