Hydronium

//haɪˈdɹəʊ.ni.əm// noun

noun ·Rare ·Advanced level

Definitions

Noun
  1. 1
    The hydrated hydrogen ion, H₃O⁺. physical

    "The case of hydronium ions (H₃O⁺) is an example of this. In the gase^([sic]) phase, hydronium is a weak acid. The data in Table 3.10 indicates that bare hydronium ions have a higher electron affinity than most metal surfaces, so a bare hydronium ion should be neutralized when it absorbs on a bare metal surface. However, a hydrated hydronium ion is a stronger acid."

Example

More examples

"The case of hydronium ions (H₃O⁺) is an example of this. In the gase^([sic]) phase, hydronium is a weak acid. The data in Table 3.10 indicates that bare hydronium ions have a higher electron affinity than most metal surfaces, so a bare hydronium ion should be neutralized when it absorbs on a bare metal surface. However, a hydrated hydronium ion is a stronger acid."

Etymology

From hydro- + onium.

Related phrases

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.