Question

Four pure water, degree of dissociation is `1.9xx10^(-9),lambda_(m)^(0)=350 Scm^(2)"mol"^(-1)` and `lambda_(m)^(0)=200S cm^(2) "mol"^(-1)`. Hence molar conductance of water is
A. `1.045xx10^(-6)S cm^(2) "mol"^(-1)`
B. `1.045xx10^(-14)Scm^(2)"mol"^(-1)`
C. `1.045xx10^(-14)Scm^(2)"mol"^(-1)`
D. `1.045xx10^(-7)S cm^(2) "mol"^(-1)`

Answer 1

Correct Answer - A
Degree of dissociation
`alpha=(lambda_(m)^(0))/(lambda_(m)^(0))`
`lambd a_(m)^(0)=alphaxx lambda_(m)^(0)`
`=1.9xx10^(-9)(350+200)`
`=1.9xx550xx10^(-9)`
`=1.045xx10^(-6)S cm^(2) "mol"^(-1)`