Saved Bookmarks
| 1. |
State Kohlrausch Law. How is it useful to determine the molar conductivity of weak electrolyte at infinite dilution? |
|
Answer» SOLUTION :Kohlraush.s law :At infinite dilution, the limiting molar conductivity of an electrolyte is equal to the some of the limiting molar CONDUCTIVITIES of its constituent ions. Calculation of molar conductance at infinite dilution of a WEAK electrolyte. It is impossible to determine the molar conductance at infinite dilution for weak electrolytes experimentally. However, the same can be calculated using Kohlraush.s Law. For EXAMPLE, the molar conductanceof `CH_(3)COOH`, can becalculated using the experimentally determined molar conductivities of strong electrolytes HCl,NaCl and `CH_(3)COONa`. `wedge_(CH_(3)COONa)^(@)=lambda_(Na^(+))^(@)+lambda_(CH_(3)COO^(-))^(@) "...(1)"` `wedge_(HCl)^(@)=lambda_(H^(+))^(@)+lambda_(Cl^(-))^(@)"...(2)"` `wedge_(NaCl)^(@)=lambda_(Na^(+))^(@)+lambda_(Cl)^(@)"...(3)"` Equation (1) + Equation (2) - Equation (3) gives. `(wedge_(CH_(3)COONa)^(@))+(wedge_(HCl)^(@))-(wedge_(NaCl)^(@))=lamda_(H^(+))^(@)+lambda_(CH_(3)COO)^(@)` `""=wedge_(CH_(3)COOH` |
|