question_answer

Equimolar solutions of the following were prepared in water separately. Which one of the solutions will record the highest pH?                                                                                                                                    [AIPMT (S) 2008]

A)  \[SrC{{l}_{2}}\]          

B)       \[BaC{{l}_{2}}\]

C)  \[MgC{{l}_{2}}\]         

D)       \[CaC{{l}_{2}}\]

Correct Answer: B

Solution :

Key Idea: As the basic nature increases, pH increases pH of base > 7 pH 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:

Therefore, the solution of  will record the highest pH.