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concentration. For example, an acid with a pH of 2 has 100 times the H⁺ concentration of an acid
with a pH of 4.
Hydrogen and Hydroxide Ion Concentration:
Acidity is determined by the concentration of hydrogen ions in solution: the higher the H⁺
concentration, the lower the pH. Conversely, a higher concentration of hydroxide ions increases
the pH, making the solution more alkaline.
Proton Transfer in Acids and Bases
Acids are classified as proton donors because they release hydrogen ions (H⁺) in solution, which
contributes to the acidic nature of the solution. Conversely, bases act as proton acceptors, taking in
the H⁺ ions that acids release. For instance, when hydrochloric acid reacts with water, water acts as
a base by accepting a proton from the acid.
Strong and Weak Acids
Definition of a Strong Acid:
A strong acid is one that fully dissociates in water, meaning it completely releases all available H⁺
ions, creating a solution with a low pH. Some common examples of strong acids include
hydrochloric acid (HCl) and sulfuric acid (H₂SO₄). For example, in solution: