Lesson Plan: Determining Purity Chemistry • Third Year of Secondary School
This lesson plan includes the objectives, prerequisites, and exclusions of the lesson teaching students how to determine the purity of a substance based on its proportion by mass and physical properties.
Objectives
Students will be able to
- understand the definition of purity and the difference between its everyday and chemical use,
- calculate the percentage purity of a substance from its mass,
- describe what an impurity is and give examples of common impurities found within substances,
- identify how to tell if a substance is pure from its melting and boiling points,
- understand the effect impurities have on the melting and boiling point of a substance,
- appreciate how there are methods to separate and obtain a pure product.
Prerequisites
Students should already be familiar with
- melting and boiling points.
Exclusions
Students will not cover
- details on the different methods to obtain a pure product; these are covered in subsequent lessons.
