1. Water is an amphoteric substance. In any sample of water some of the moles

In any sample of water some of the molecules perform acid-

base reactions with each other. This is called the autoionization of water. Write a chemical reac

tion showing the acid-base reaction of two water molecules.

2H₂O (l) ⇄ H₃O⁺ (aq) + OH⁻ (aq)

Explanation:

The autoionization of water is defined as a chemical reaction where there is an equilibrium in which two water molecules react producing an hydronium ion and a hydroxide ion. This is also defined as the autoprotolysis of water, and is based on its amphoteric nature.

The substance that can donate protons as well as receive them is defined as amphoteric. In this way, the water behaves amphoteric as it donates a proton as an acid of Brownsted Lowry or if it receives a proton, being a base.

NH₃ + H₂O ⇄ NH₄ + OH⁻ Kb

In this case, water behaves as an acid, it donates the proton to ammonia (a base)

CH₃COOH + H₂O ⇄ CH₃COO⁻ + H₃O⁺ Ka

For this case, water behaves as a base, it recieves the proton from the acetic acid (acid)