The ionization constant of HF is 3.2×10-4. Which of the following is the correct value of degree of dissociation if concentration is 0.02 M?

Cα21-α=Ka                        The solution is not very dilute0.02×α21-α=3.2×10-4      (given)α21-α=1.6×10-2α2+1.6×10-2α-1.6×10-2=0α=-1.6×10-2±1.6×10-22+4×1.6×10-22=-1.6×10-2+6.4×10-22                                   1.6×10-22 neglected=-0.016+0.25320.12Alternatively,For dilute weak acid, α=KC                                   α=3.2×10-40.02=1.6×10-2=0.126