Rahul set-up an experiment to find resistance of aqueous KCl solution for different concentrations at 298 K using a conductivity cell connected to a…

Rahul set-up an experiment to find resistance of aqueous $\displaystyle \mathrm{KCl}$ solution for different concentrations at $\displaystyle 298$ K using a conductivity cell connected to a Wheatstone bridge. He fed the Wheatstone bridge with a.c. power in the audio frequency range $\displaystyle 550$ to $\displaystyle 5000$ cycles per second. Once the resistance was calculated from null point he also calculated the conductivity K and molar conductivity $\displaystyle \mathbf{\Lambda}_m$ and recorded his readings in tabular form.

S.No.	Conc.(M)	$\displaystyle k$ S cm$\displaystyle ^{-1}$	$\displaystyle \mathbf{\Lambda}_m$ S cm$\displaystyle ^2$ mol$\displaystyle ^{-1}$
1.	$\displaystyle 1.00$	$\displaystyle 111.3 \times 10^{-3}$	$\displaystyle 111.3$
2.	$\displaystyle 0.10$	$\displaystyle 12.9 \times 10^{-3}$	$\displaystyle 129.0$
3.	$\displaystyle 0.01$	$\displaystyle 1.41 \times 10^{-3}$	$\displaystyle 141.0$

Answer the following questions :

Why does conductivity decrease with dilution ?

If $\displaystyle \mathbf{\Lambda}_m^{\circ}$ of $\displaystyle \mathrm{KCl}$ is $\displaystyle 150.0$ S cm$\displaystyle ^2$ mol$\displaystyle ^{-1}$, calculate the degree of dissociation of $\displaystyle 0.01$ M $\displaystyle \mathrm{KCl}$.

If Rahul had used $\displaystyle \mathrm{HCl}$ instead to $\displaystyle \mathrm{KCl}$ then would you expect the $\displaystyle \mathbf{\Lambda}_m$ values to be more or less than those per $\displaystyle \mathrm{KCl}$ for a given concentration. Justify.

Amit a classmate of Rahul repeated the same experiment with $\displaystyle \mathrm{CH_3COOH}$ solution instead of $\displaystyle \mathrm{KCl}$ solution. Give one point that would be similar and one that would be different in his observations as compared to Rahul.