Lesson: The pH Scale Chemistry • First Year of Secondary School

Students will be able to

• recall that pH is a relative measure of acidity and basicity,
• define pH in qualitative terms as a logarithmic measure of the concentration of ions,
• draw and interpret a pH scale including common acids and bases,
• identify acids and bases from their pH values,
• estimate the pH values of common acids and bases (e.g., lemon juice),
• understand and explain the change in pH during an experiment (e.g., adding powdered calcium hydroxide to dilute hydrochloric acid),
• describe the use of simple indicators to provide an approximation of the pH of a solution (e.g., litmus paper, universal indicators).