Which have maximum $\mathrm{pH}$ in aqueous solution

Which have maximum $\mathrm{pH}$ in aqueous solution
  1. $\mathrm{NaOCl}$
  2. $\mathrm{NaClO}_{4}$
  3. $\mathrm{NaClO}_{3}$
  4. $\mathrm{NaClO}_{2}$

Solution

Maximum pH means most basic. Therefore the solution of $\mathrm{NaClO}$ (salt of a strong base with the weakest acid out of $\mathrm{HClO}, \mathrm{HClO} 2, \mathrm{HClO} 3$, andHClO4) in water will be most basic and as such will have the highest $\mathrm{pH}$.
$\mathrm{NaClO}$ has the maximum $\mathrm{pH}$ because the acidic strength decreases with decreasing $\mathrm{O}$ atoms in oxyacids . Since $\mathrm{NaClO}$ has the lowest oxygen atom among given options, it will have least acidic strength and hence, a maximum pH.

Asked in: JEE-TOPICTESTS-CHEMISTRY

Practice more EQUILIBRIUM questions on Aicharya