At 291 K, the molar conductivities at infinite dilution of NH_(4)Cl, NaOH and NaCl are 129.8, 217.4 and 108.9" S " cm^(2) mol^(-1) respectively. The molar conductivity of a centinormal solution of NH_(4)OH is 9.33" S "cm^(2)mol^(-1). The percentage dissociation of NH_(4)OH at this dilution and the dissociation constant of NH_(4)OH are :

At 291 K, the molar conductivities at infinite dilution of NH_(4)Cl, N

1.	At 291 K, the molar conductivities at infinite dilution of NH_(4)Cl, NaOH and NaCl are 129.8, 217.4 and 108.9" S " cm^(2) mol^(-1) respectively. The molar conductivity of a centinormal solution of NH_(4)OH is 9.33" S "cm^(2)mol^(-1). The percentage dissociation of NH_(4)OH at this dilution and the dissociation constant of NH_(4)OH are :
Answer» `3.92%,1.599xx10^(-5)` `6.92%,3.599xx10^(-5)` `3.92%,4.599xx10^(-2)` `9.92%,1.599xx10^(-5)` Solution :(a) `Lambda_((NH_(4)OH))^(@)=Lambda_((NH_(4)CL))^(@)+Lambda_((NaOH))-Lambda_((HCL))^(@)` `=129.8+217.4-108.9=238.3" s "cm^(2)mol^(-1)` Degree of dissociation `(alpha)=(Lambda_(C ))/(Lambda^(@))=((9.33" S "cm^(2)mol^(-1)))/((238.3" S "cm^(2)mol^(-1)))` `=0.0392=0.0392xx100=3.92%` Dissociation constant `NH_(4)OH hArr NH_(4)^(+)+OH^(-)` `{:("Initial CONC".,C,0,0),("Equilibrium conc".,C-Calpha,Calpha,Calpha),(,C(1-alpha),Calpha,Calpha):}` `K_(a)=(CalphaxxCalpha)/(C(1-alpha))=(Calpha^(2))/(1-alpha)` `=((0.01)xx(0.0392))/((1.0.0392))=1.599xx10^(-5)`