Question

Compouter the m olar conducitivity of a solution of `MgCl_(2)` at infinite dilution. Given that `lambda_(Mg)^(2+)=106.12ohm^(-1)cm^(2)"mol"^(-1)`
`lambda _(Mg)^(2+)=106.12ohm^(-1)cm^(2)"mol"^(-1)`
A. 182.46`ohm^(-1)cm^(2)"mol"^(-1)`
B. `258.8ohm^(-1)cm^(2)"mol"^(-1)`
C. `212.24ohm^(-1)cm^(2)"mol"^(-1)`
D. `152.68ohm^(-1)cm^(2)"mol"^(-1)`

Answer 1

Correct Answer - B
`426.1=lambda_((H^(+))^(0))+lambda_((CH_(3)COO^(-)))^(0)` .......(ii)
`126.5 =lambda_((Na^(+)))^(0)+lambda_((Cl^(-))^(0)`
Adding eqn. (i) and (ii) and sub tracting eqn.
iii we get
`lambda_((H^(+))^(0))+lambda_((CH_(3)COO^(-)))^(0)=426.1+91.0-126.5`
`=390.6ohm^(-1)cm^(2)"mol"^(-1)`