Can the pH scale be utilized for all acids (Arrhenius, Bronsted-Lowery, and Lewis) ? Give examples of substances from each definition category that can/cannot use the pH scale and explain your reasoning.

Before proceeding to answering the questions, let us go over some definitions.

pH scale: The pH scale measures how acidic or basic a substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic.

pH stands for Potential of Hydrogen. It refers to the hydrogen ion concentration in a solution.

The keywords being; Hydrogen Ion concentration.

A Bronsted-Lowry acid is a chemical species that donates one or more hydrogen ions in a reaction.

A Lewis acid is any substance that can accept a pair of nonbonding electrons. It is an electron pair acceptor.

An Arrhenius acid is a substance that dissociates in water to form hydrogen ions or protons.

Based on the definitions of given above, it is obseved that both Bronsted lowry and arrhenius acids deals with hydrogen ions. Hence both of this acids can be measured using the pH scale. The lewis acid on the other hand do not necessarily contain hydrogen ions, hence the pH scale cannot be utilized for it.

Examples includes;

Arrhenius acid; Nitric Acid - HNO3 etc

Lewis acid; boron trifluoride (BF3) and aluminum fluoride (AlF3) etc

Bronsted lowry acid; HCl etc