Question

Which of the following expressions correctly represents the equivalent conductance at infinite dilution of `Al_(SO_(4_(3))`. Given that `overset(@)Lambda_(Al^(3+))` and `overset(@)Lambda_(SO_(4)^(2-))` are the equivalent conduactance at infinite dilution of the respective ions?
A. `2Lambda_(Al^(3+))^(@)+3Lambda_(SO_(4)^(2-))^(@)`
B. `Lambda_(Al^(3+))^(@)+Lambda_(SO_(4)^(2-))^(@)`
C. `(Lambda_(Al^(3+))^(@)+Lambda_(SO_(4)^(2-))^(@)) xx 6`
D. `(1)/(3)Lambda_(Al^(3+))^(@)+(1)/(2)Lambda_(SO_(4)^(2-))^(@)`

Answer 1

Correct Answer - B
According to Kohlrausch law of independent migration of ions, the equivalent conductance of any electroyte at infinite dilution is the sum of equivalent conductances of the ions furnished by the electrolyte. Thus
`Lambda_(eq.)^(@)[Al_(2)(SO_(4))_(3)] = Lambda_(eq.)^(@)(Al^(3+))+Lambda_(eq.)^(@)(SO_(4)^(2-))`