The `lamda^(@)` values of NaCl and `NanO_(3)` are 126.5 and `121.6S" "cm^(2)mol^(-1)` respectively. The `lamda^(@)` value of `NO_(3)^(-)` ion is 76.3 S `cm^(2)mol^(-1)` calculate `lamda^(@)(Cl^(-))`.

Explanation

`NaCl rarr Na^(+) + Cl^(-), lamda^(0) = 126.5 S cm^(2) mol^(-1)` …(1)
`NaNO_(3) rarr Na^(+) + NO_(3)^(-), lamda^(@) = 121.6 S cm^(2) mol^(-1)` …(2)
`NO_(3)^(-), lamda^(@) = 76.3 S cm^(2) mol^(-1)` …(3)
To calculate `lamda^(@)` for `Cl^(-)`
`(1)- (2) + (3)= 126.5- 121.6 + 76.3= 81.2 S cm^(2) mol^(-1)`