0.1 M solution of an electrolyte `A^(+)B^(-)` placed in a conductivity cell wilth electrodes 4 cm apart and each with area of cross-section equal to 2 sq cm was found to have a resistance of `200 Omega`. The molar conductivity of the solution will be

Options

A. `25cm^(2)//Omega`
B. `100 cm^(2)//Omega`
C. `0.25 cm^(2)//Omega`
D. `400 cm^(2)//Omega`

Answer

B

Explanation

`k=1/Rxxl/a=1/200xx4/2`
`=1/100 Omega^(-1)cm^(-1)`
`Lambda_(m)=kxx1000/("molarity")=1/100xx1000/0.1`
`=100cm^(2)//Omega`