[hiswifetheirmom]

Tell why vinegar (0.8M acetic acid) reacts much more slowly with zinc and marble chips than 0.8M hydrochloric acid, even though both acids have about the same total concentrations?

[cth]

Because HCl is a strong acid, while acetic acid is a weak acid.

Strong acid are completely deprotonated in water: you find Cl^- and H₃O⁺ floating around in solution, but no undissociated HCl.

Weak acids are not completely deprotonated in water: you have an equilibrium between CH₃CO₂H and CH₃CO₂^-. Therefore, some part of the acetic acid can't react with zinc. The reaction is slower.

[tinapratiwi]

yes thats true cth....
I agree with you...