The ionization constant of acetic acid is 1.74xx10^(-5). Calculate the degree of dissociation of acetic acid in its 0.05 M solution. Calculate the concentration of acetate ions in the solution and its pH .

The ionization constant of acetic acid is 1.74xx10^(-5). Calculate the

1.	The ionization constant of acetic acid is 1.74xx10^(-5). Calculate the degree of dissociation of acetic acid in its 0.05 M solution. Calculate the concentration of acetate ions in the solution and its pH .
Answer» Solution :`{:(,CH_(3) CO OH,hArr,CH_(3)CO O^(-),+,H^(+),,),("INITIAL",C,,0,,0,,),("At eqm.",C-C alpha,,C alpha,,C alpha ,,):}` `K_(a)=(C alpha. C alpha)/(C(1-alpha))=(C alpha^(2))/(1-alpha) ~= C alpha^(2)` `alpha = sqrt((K_(a))/(C))` (or directly by Ostwald DILUTION law) `=sqrt((1.74xx10^(-5))/(0.05))=sqrt(3.48xx10^(-4))=1.86xx10^(-2)` `[CH_(3)CO O^(-)] = C alpha = 0.05 xx (1.86xx10^(-2))=9.3xx10^(-4)M` `[H^(+)]=C alpha = 9.3 xx 10^(-4)` `pH = - log [H^(+)]=- log (9.3xx10^(-4))=3.03`