Question

Can pure hydronium exist? If not, why not? It seems to me (and I am no chemistry expert) like pure hydronium should have the theoretical maximum acidity or minimum pH that a substance can reach. Can't, for example, we obtain pure hydronium if we could somehow produce a container with a certain amount of pure ionized hydrogen (H⁺), and mixed it with an equal number of moles of water (H₂O) to produce pure hydronium (H₃O⁺)? Or if that example is too theoretical, couldn't we also simply mix an equal number of moles of hydrochloric acid (HCl) and water (H₂O) to produce something close enough, hydronium (H₃O⁺) with chloride ions (Cl⁻)?

Answer 1

Hydronium ions (H3O+) exist in aqueous solutions and are formed when a water molecule (H2O) accepts a hydrogen ion (H+). However, pure hydronium does not exist as a separate substance because the hydronium ion is always found in combination with other species. In pure water, the concentration of hydronium ions is very low, making water essentially neutral with a pH of 7.

Step-by-step explanation:

Hydronium ions (H3O+) exist in aqueous solutions and are formed when a water molecule (H2O) accepts a hydrogen ion (H+). However, pure hydronium does not exist as a separate substance because the hydronium ion is always found in combination with other species. In pure water, the concentration of hydronium ions is very low, making water essentially neutral with a pH of 7.

When hydrochloric acid (HCl) is dissolved in water, the hydrogen ion (H+) from HCl attaches to a water molecule and forms the hydronium ion (H3O+). So, if you mix hydrochloric acid and water in equal moles, you will have a solution containing hydronium ions with chloride ions (Cl-) from the hydrochloric acid.