Question

If 1M of HCl is placed with 1L of water, how would the amount of H3O+ compare to that of a solution made from 1M of acetic acid placed in 1L of water?

Answer 1

The solution with `HCl` would have a much greater concentration of `H_3O^+` ions than the solution with acetic acid.

Explanation:

First, let's establish that `HCl`, or hydrochloric acid, is a strong acid, and that `CH_3COOH`, or acetic acid, is a weak acid.

They're both acids, which means that, according to the Bronsted-Lowry definition, both of them will donate `H^+` ions in an aqueous solution.
These `H^+` ions will form the hydronium ion, `H_3O^+`, with water molecules because `H_2O` has `2` lone pairs on the oxygen atom:

A strong acid is one that almost completely dissociates to donate `H^+` ions, and a weak acid is one that only somewhat dissociates.

So, if the same amount of a strong acid (`HCl`) and a weak acid (`CH_3COOH`) were placed in the same amount of water, the amount of `H_3O^+` concentration formed as a result of `H^+` ions being donated would be greater in the solution with `HCl`.