Question

Explain the variation of molar conductivity with concentration of strong and weak electrolytes

Answer 1

Explanation:

Both specific conductance or conductivity and molar conductivity change with concentration of the electrolyte. Conductivity of an electrolyte decreases with the decrease in concentration both for weak and strong electrolytes, whereas molar conductivity increases with decrease in concentration.

Answer 2

Answer:

i) As the dilution of an electrolytic solution increases, the dissociation of the clcctrolyte increases, hence the total number ot 1ons increases, theretore, the molar conaucuvity inereases.

ii) The increase in molar conductivity with increase in dilution or decrease in concentration is different for strong and weak clectrolytes.

iii) On dilution, the molar conductivity of strong eleotrolytes increases rapidly and approaches to a maxium imiung value at nimte diluion or zero concentration and represented as ^infinity or A_o Or ^^0.

Iv) In case of weak electrolytes which dissociate less as compared to strong electrolytes, the molar conductivity is low and increases slowly in high concentration region, but increases rapidly at low concentration or high dilation. This is because the extent of dissociation increases with dilution rapidly.

(v) ^_o values for strong electrolytes can be obtained by extrapolating the linear graph to zero concentration (or ininite dilution). However ^_o 1or the weak electrolytes cannot be obtained by this mcihod, since the graph increases exponentially at very high dilution and does not intersect ^_m axis at zero concentration.