The molar ionic conductivities of NH4+ and OH- at infinite dilution are 72 and 198 ohm-1 cm2 respectively. The molar conductivity of a centinormal NH4OH solution at the same temperature is found to be 9 ohm-1 cm2. The percentage dissociation of NH4OH at this concentration will be

Question

The molar ionic conductivities of NH4+ and OH- at infinite dilution are 72 and 198 ohm-1 cm2 respectively. The molar conductivity of a centinormal NH4OH solution at the same temperature is found to be 9 ohm-1 cm2. The percentage dissociation of NH4OH at this concentration will be (A) 3.33% (B) 7.14% (C) 12.5% (D) 4.54%

Tardigrade Admin · Accepted Answer

∧mâ (NH4OH)=λâNH4+ +λâOH- =72+198=270 ohm-1 cm2 α=( Lambdamc/ Lambdamâ)=(9/270)=(1/30)=3.33 %.

Q. The molar ionic conductivities of NH4+​ and OH− at infinite dilution are 72 and 198 ohm−1cm2 respectively. The molar conductivity of a centinormal NH4​OH solution at the same temperature is found to be 9 ohm−1cm2. The percentage dissociation of NH4​OH at this concentration will be

3.33%

7.14%

12.5%

4.54%

∧m∘​(NH4​OH)=λNH4+​∘​+λOH−∘​ =72+198=270ohm−1cm2 α=Λm∘​Λmc​​=2709​=301​=3.33%.

$\land_{m}^{\circ} (N H_{4} O H) = λ_{N H_{4}^{+}}^{\circ} + λ_{O H^{-}}^{\circ}$
$= 72 + 198 = 270 o h m^{- 1} c m^{2}$
$α = \frac{Λ _{m}^{c}}{Λ _{m}^{\circ}} = \frac{9}{270} = \frac{1}{30} = 3.33%.$