Answer:
c) more OH⁻ ions than H₃O⁺ ions
Explanation:
A substance with a PH of 9 implies that it has more OH⁻ ions than H₃O⁺ ions.
Such substances are said to be an alkaline or a base.
A base is a substance the produces excess hydroxyl ion in aqueous solutions.
An acid will produce excess hydroxonium ions in a solution.
So, the pH scale is used to indicate whether a substance is an acid or base or non of them.
Acids have pH of less than 7
Bases have pH of > 7