The pH scale can be used to describe if a substance is strong or weak, but not dilute or concentrated. Explains why from The Hutchinson Unabridged Encyclopedia with Atlas and Weather Guide
What is the pH scale? This is a scale from 0 to 14. It is used to describe a substance as acid, neutral, or alkali. Numbers below 7 are acid, 7 is neutral (neither acid nor alkali), and numbers above 7 are alkali.
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