Acidity - GCSE Chemistry Definition

Acidity refers to the measure of how acidic a substance is and is determined by the concentration of hydrogen ions (H⁺) in a solution. In the context of the GCSE Chemistry course, substances with high acidity have low pH values, typically below 7, with lower numbers indicating stronger acidity.

Acids are chemicals that can donate H⁺ ions to a solution, and common examples include hydrochloric acid and sulphuric acid. Acidity can have various effects, such as impacting the taste of foods and the rate of corrosion in materials. Understanding acidity is crucial for exploring chemical reactions, such as neutralisation, where an acid reacts with a base to form a salt and water.