Question

Calculate `^^_(m)^(0)` for `CaCl_(2) and MgSO _(4)` from the data given in Table `3.4.`

Answer 1

We kniow from Kohlrausch law that
`^^_(m(CaCl_(2)))^(0)=^^_(Ca^(2+))^(0) +2 lamda_(Cl)^(0) =119.0 S cm^(2) mol ^(-1)+ 2 (76.3) S cm ^(2) mol ^(-1)`
`=(119.0+152.6) S cm ^(2) mol ^(-1)`
`=271.6 S cm ^(2) mol ^(-1)`
`^^_(m(Mg SO_(4)))^(0)=lamda _(Mg ^(2+))^(0)+ lamda _(SO_(4)^(2-))^(0) =106.0 S cm ^(2) mol ^(-1) + 160.0 S cm^(2) mol ^(-1)`
`=266 S cm^(2) mol^(-1)`