Q Resistance of a conductivity cell filled with a solution of an electrolyte of concentration 0 1M is 100 - Chemistry - The p-Block Elements

Question

Q Resistance of a conductivity cell filled with a solution of an
electrolyte of concentration 0 1M is 100 Ω The conductivity of
this solution is 1 29 S m-l Resistance of the same cell
when filled with 0 02M of the same solution is 52 Ω The molar
conductivity of 0 02M solution of the electrolyte will be
1) 12 4 x S 10-4 m2 mol-l
2) 124 x 10-4 S m2 mol-l
3) 1240 x 10-4 S m2 mol-l
4) 1 24 x 10-4 S m2 mol-l

Arnab · Accepted Answer

Cell constant can be calculated using 0 1 M KCl
= κ × R
= 0 0129 * 100
= 1 29 cm-1
Calculating conductivity of 0 02 M KCl solution
κ = Cell constant / Resistance
= 1 29 / 520
= 2 48 * 10-3 S cm-1
Therefore, molar conductivity:
Λm = 103 κ / M
= 103 * 2 48 * 10-3/0 02
= 124 S cm2 mol-1

= 
124 x 10-4

S m2 mol-1
â€‹
So, option (2) is correct