Accumulation of lactic acid (HC3H5O3), a monobasic acid in tissues leads to pain and a feeling of fatigue. In a 0.10 M aqueous solution, lactic acid is 3.7% dissociates. The value of dissociation constant, Ka, for this acid will be
The reaction can go to completion by removing OH$$-$$ ions by adding
A
CO2
B
SO2
C
HCl
D
KOH
Explanation
KOH is the base thus, it gives OH–
ions thus
it cannot remove OH–
ions from reaction mixture
but it adds on the concentration of OH–
ions.
So,
an acid must be added but if a strong acid is added
to the reaction mixture then in acidic condition the
MnO4–
formed reduces to give Mn2+ thus, HCl
which is a strong acid and SO2 which on treating
with water forms a strong H2SO4 cannot be used
for this purpose.
Thus, CO2 which forms H2CO3 a
weak acid reacts to remove OH–
but not that much
acidic that MnO4–
undergo reduction. Thus, CO2 is
used for this reaction for completion.
Questions Asked from Equilibrium
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