30 ! acid: pka: h20 15.7 nh3 38 hcl -8 nh4+ 9.2 given the list of pka values, which acid will have the largest amount of conjugate base present in the solution at equilibrium? h2o nh3 nh4+ hcl

Answer is: HCl (hydrochloric acid) will have the largest amount of conjugate base.

Hydrochloric acid is the strongest acid present in this question, because it has largest Ka value:
pKa(HCl) = -8.
Ka(HCl) = 10∧(-pKa).
Ka(HCl) = 10⁸.
Chemical dissotiation of hydrochloric acid:
HCl(aq) → H⁺(aq) + Cl⁻(aq).
Ka(HCl) = [H⁺]·[Cl⁻] / [HCl].
Concentration of Cl⁻ ions (conjugate base of hydrochloric acid) is very high.

The answer to this question is HCL. Since pKa = -log[Ka], we have
                                Ka = 10^(-pKa)
so with HCL, pKA = -8 and so
                                Ka = 10^(-(-8)) = 10^8
which is a very large Ka value implying full completion of reaction.