Redox Reactions And Electrochemistry Ques 734
Question: Resistance of a conductivity cell filled with a solution of an electrolyte of concentration 0.1 M is 100 ohm. The conductivity of this solution is 1.29 S/m. Resistance of the same cell filled with 0.02 M of the same solution if the electrolyte is 520 ohm. The molar conductivity of 0.02 M solution of electrolyte would be:
Options:
A) $ 124\times {10^{-4}}S-m^{2}/mol $
B) $ 1240\times {10^{-4}}S-m^{2}/mol $
C) $ 1.24\times {10^{-4}}S-m^{2}/mol $
D) $ 12.4\times {10^{-4}}S-m^{2}/mol $
Show Answer
Answer:
Correct Answer: A
Solution:
[a] at $ c=0.1,M; $ $ \frac{l}{a}=kR=1.29\times 100 $ at $ c=0.02M; $ $ \kappa =\frac{\ell }{a\times R}=\frac{1.29\times 100}{520}=0.248,S/m $ Also, $ \Lambda =\frac{k}{M( in,mol/l )}=\frac{k}{M\times 10^{3}( in,mol/m^{3} )} $ $ =\frac{0.248}{0.02\times 10^{3}}=124\times {10^{-4}}Sm^{2}/mol $
