question_answer

Which has highest pH?                                                                                                    [AIPMT 2002]

A)  \[C{{H}_{3}}COOK\]              

B)  \[N{{a}_{2}}C{{O}_{3~~}}\]

C) \[N{{H}_{4}}Cl\]  

D)    \[NaN{{O}_{3}}\]

Correct Answer: B

Solution :

is inversely proportional to hydrogen ion concentration. As concentration of  decreases pH increases and vice versa.

Ammonium chloride  is a salt of weak base and strong acid. So, its aqueous solution will be acidic as

So, pH of  is less than 7.

(Sodium nitrate) is the salt of strong acid and strong base. So, its aqueous solution is neutral as

So, pH of is 7.

(Potassium acetate) is a salt of strong base and weak acid, its aqueous solution will be basic and pH value will be

(Sodium carbonate) is a salt of strong base and weak acid. Its aqueous solution is also basic and its pH value will be more than 10.