Video narration
Why do acids need more than one classification? One label cannot tell you everything about an acid. Think of lemon juice: its acid can be described from several viewpoints. First, source: acids may be natural, like citric acid in lemon; mineral, or inorganic, like hydrochloric acid; or organic, such as acetic acid. These labels can overlap. Next is strength. It depends on ionization: how much acid forms ions in water. Strong acids ionize more completely; weak acids only partly. Basicity asks a different question: how many replaceable hydrogen ions, written H-plus, can one acid molecule release? Here is the important flip: strong does not mean concentrated. Strength describes ionization. Concentration describes how much acid is present in a given amount of solution. So why four classifications? Source, strength, basicity, and concentration each answer a different question. Acids are not on one scale; one acid can carry several labels.