Question Video: Identifying the Term Used to Describe Water in the Formation of the Hydronium Ion Chemistry • Second Year of Secondary School

Video Transcript

Two water molecules can react to produce a hydronium ion, H3O+, and a hydroxide ion, OH−. The formation of the hydronium ion can be simplified to the reaction shown. Which of the following terms can be used to describe the water in the reaction shown? (A) Lewis base, (B) Lewis acid, (C) hypervalent, (D) electrophile, or (E) conjugated.

Covalent bonds form when atoms share one or more valence electrons. Most covalent bonds contain electrons from both bonding atoms. Some covalent bonds result from both shared electrons originating from only one of the bonding atoms. Coordinate covalent bonds are covalent bonds where the pair of electrons forming the bond is donated from one atom only.

Atoms that receive donated pairs of electrons are known as acceptors. They can also be called Lewis acids. Electron pair donors are known as Lewis bases.

In the question, we see that an electron pair is being donated from water to the adjacent hydrogen ion. This produces the hydronium ion. As water is donating a pair of electrons, it is behaving as a Lewis base.

Therefore, the term that can be used to describe water in the reaction shown is answer choice (A), Lewis base.