Question

The correct order of equivalent conductances at infinite dilution in water at room temperature for $H^{+},K^{+},C{H}_{3}CO{O}^{-}$ and $H{O}^{-}$ ions is

• A. $H{O}^{-}>H^{+}>K^{+}>C{H}_{3}CO{O}^{-}$
• B. $H^{+}>H{O}^{-}>K^{+}>C{H}_{3}CO{O}^{-}$
• C. $H^{+}>K^{+}>H{O}^{-}>C{H}_{3}CO{O}^{-}$
• D. $H^{+}>K^{+}>C{H}_{3}CO{O}^{-}>H{O}^{-}$

Answer 1

Answer: (B)

Equivalent conductance $\left({\Lambda }_{eq}\right)$ is defined as the conducting power of all the ions produced by one gram equivalent of an electrolyte in a given solution.ln case of weak electrolytes (as $C{H}_{3}COO{H}_{1}N{H}_{4}OH,AgCl$ etc.), ionisation is very
small compared to strong electrolytes (as $KCl$, $NaOH$ etc.), hence ${\Lambda }_{\text{eq }}$ of weak electrolyte is low. Moreover, ionisation of $H^{+}$is maximum among given ions. Thus, correct of order of ${\Lambda }_{\text{eq }}$ is
$H^{+}>O{H}^{-}>K^{+}>C{H}_{3}CO{O}^{-}$