2. Ans :-
Acid-base reaction of Na2CO3 or CO32- with water is :
CO32- (aq) + H2O (l) <------------------> HCO3- (aq) + OH- (aq) , Kb = 1.8 x 10-4 ................(1)
Expression of base dissociation constant (Kb) is :
Kb = [HCO3- ].[OH-] / [CO32-]
Similarly,
Acid-base reaction of C6H5NH3+ with water is :
C6H5NH3+ (aq) + H2O (l) <------------------> C6H5NH2 (aq) + H3O+ (aq) , Ka = Kw/Kb = 1.0 x 10-14 / 4.2 x 10-10 = 2.38 x 10-5 ................(2)
Expression of acid dissociation constant (Kb) is :
Ka = [C6H5NH2 ].[H3O+] / [C6H5NH3+]
Self ionization water is :
H2O (l) + H2O (l) <------------------> H3O+ (aq) + OH- (aq) , Kw = 1.0 x 10-14 ................(3)
Expression of ionic product of water (Kw) is :
Kw = [H3O+].[OH- ]
Adding equations (1) and (2) and then subtract it in equation (3) , we have the required chemical equation is :
CO32- (aq) + C6H5NH3+ (aq) <-----------------> HCO3- (aq) + C6H5NH2 (aq) , Kc = ?
Expression of equilibrium constant i.e. Kc is :
Kc = [HCO3- ].[C6H5NH2] / [CO32-].[C6H5NH3+ ]
Now, the relationship between Kc , Ka and Kb is :
Kc = Ka x Kb / Kw
Kc = (2.38 x 10-5).(1.8 x 10-4 ) / (1.0 x 10-14)
Kc = 4.28 x 105
Hence, equilibrium constant (Kc) of the required reaction is = 4.28 x 105 |
Q2 & 4 please?? only question 2. top 2 equations r not for this question. C6H4COH...
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