Ka for acetylsalicylic acid (aspirin), hc9h7o4, is 3.00×10-4. ka for hydrocyanic acid, hcn, is 4.00×10-10. ka for benzoic acid, c6h5cooh, is 6.30×10-5. what is the formula for the strongest acid?

Ka is the acid-dissociation constant of each of these acids. It represents the proportion of a given amount of the acid that dissociates from the acid into H+ and it’s conjugate base when dissolved into solution.

The concentration of H+ determines the strength of the acids, so those acids with the biggest Ka values are the strongest acids.

Your order would be:
Aspirin (strongest)
Benzoic
Hydrocyanic (weakest)

Cause its being chemically applied?