The active ingredient formed by aspirin in the body is salicylic acid, \({C_6}{H_4}OH\left( {C{O_2}H} \right)\). The carboxyl group \(\left( { - C{O_2}H} \right)\)acts as a weak acid. The phenol group (an OH group bonded to an aromatic ring) also acts as an acid but a much weaker acid. List, in order of descending concentration, all of the ionic and molecular species present in a \(0.001M\) aqueous solution of \({C_6}{H_4}OH\left( {C{O_2}H} \right)\)

A weak acid is any acid that is not a strong acid. When a weak acid dissociates, the acid becomes stronger.

All the ionic and molecular species present in a 0.001 M aqueous solution of\({C_6}{H_4}OH\left( {C{O_2}H} \right)\)in the order of descending concentrations are\({H_2}O > {C_6}{H_4}OH\left( {C{O_2}H} \right) > {H^ + } > {C_6}{H_4}OH\left( {CO_2^ - } \right) > {C_6}{H_4}{O^ - }\left( {CO_2^ - } \right) > O{H^ - }.\)

After the water ionized form of salicylic acid it is weak acid and there is more molecule dissociate. This is followed by the salicylic acid, which have \({H^ + }\) ions and have a higher concentration of the ionized form. Both \({C_6}{H_4}OH\left( {C{O_2}H} \right)\;and {C_6}{H_4}OH\left( {CO_2^ - } \right)\) molecules can release a proton. After \({H^ + }\)ions, we have \({C_6}{H_4}OH\left( {CO_2^ - } \right), followed by \;{C_6}{H_4}{O^ - }\left( {CO_2^ - } \right)\). The \(C{O_2}H\) group is a stronger acid than the \(OH\) group and likely to ionize. \(O{H^ - }\) ions are a weak acidic solution. Both \(O{H^ - } and\;{H^ + }\) ions in every solution’s relative concentration determines whether a solution is acidic or basic.