The _____ scale reports how acidic or basic a solution is.

The _____ scale reports how acidic or basic a solution is.

• A. pH
• B. pKa
• C. pKb
• D. Ka

Answer: (A)

Measuring how acidic or basic a solution is is done with the pH scale. pH = -log10[H+], so higher hydrogen ion concentration makes the pH lower (more acidic) and lower hydrogen ion concentration makes the pH higher (more basic). Neutral water at room temperature sits around pH 7; values below 7 are acidic and values above 7 are basic. The other terms describe how strongly an acid or base dissociates (Ka, pKa, Kb, pKb) and are useful for understanding strength and buffering, but they don’t directly report the current acidity or basicity of a solution.

Measuring how acidic or basic a solution is is done with the pH scale. pH = -log10[H+], so higher hydrogen ion concentration makes the pH lower (more acidic) and lower hydrogen ion concentration makes the pH higher (more basic). Neutral water at room temperature sits around pH 7; values below 7 are acidic and values above 7 are basic. The other terms describe how strongly an acid or base dissociates (Ka, pKa, Kb, pKb) and are useful for understanding strength and buffering, but they don’t directly report the current acidity or basicity of a solution.