(a) Define the terms conductivity and molar conductivity for the solution of an electrolyte.
Comment on their variation with temperature
(b) The measured resistance of a conductance cell was 100 ohms. Calculate (i) the specific conductance and (ii) the molar conductance of the solution
`(KCl=74.5 g mol^(-1)` and cell constant =1.25 `cm^(-1))`

Explanation

(a) Conductivity of a solution is equal to the conductance of a solution of 1cm length and corss section area of 1 square cm it may also be define as the conductance of ine centimeter cube of the conductor .It is represeted by the symbol kappa (k) methmatically we can write
`k=GxxG^(*)` conductance ,`G^(*)`=cell constant
The unit of K is `ohm^(-1) cm ^(-1)` or S `cm^(-1)`
The conductivity K of an electrolytic solution depends on the concentration of the electrolyte nature of solvent and temperature .molar conductivity molar conductivity of a solution at a given concentration is the conductance of the volume v of solution containing one mole of electrolyt e between two electrodes with area of cross section a and distacne of unit length
(b) R=100 ohms
Cell constant =12.5 `cm^(-1)`
Specific conductivity (k) observed = conductance `xx` cell constant
`=(1)/(100)omega^(-1)xx12.5 cm^(-1)`
`=(1.25)/(100)omega^(-1)cm^(-1) =0.0125 omega^(-1)cm^(-1)`
molar conductivity (m)=`(kxx1000)/("malarity")=(0.125xx1000cm^(3)L^(-1))/(75.5 g mol^(-1))`
`=(12.5)/(14.5xx100)=125=(12.5)/(0.74)=(1.25)/(0.74)=16.89 cm^(2)//mol`