Final answer:
The major species in the solution made by mixing HCN and HC2H3O2 are the conjugate base of HC2H3O2, C2H3O2-, which dominates due to its increased ionization compared to HCN.
Step-by-step explanation:
In the solution made by mixing HCN and HC2H3O2, the major species present will depend on the relative concentrations of the two acids and their respective dissociation constants. HCN is a weak acid with a smaller Ka value compared to HC2H3O2, so in a solution where the two acids are mixed, the major species would be the conjugate base of HC2H3O2, which is C2H3O2-. This is because HC2H3O2 would ionize more than HCN, resulting in a higher concentration of C2H3O2- ions.
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