Unit 2 Classification of matter : Pure substance and Mixture At the last unit, you learned what MATTER, ELEMENTS and COMPOUNDS are. Matter can be classified into PURE SUBSTANCE and MIXTURE but what are they? What is a pure substance and a mixture ? 1. Look at the pictures, fill the table and try to write what you think a "Pure substance" is. Picture's Name of the object number 1 2 3 H₂0 H₂0 H₂0 Definition Element or compound ? Au Au Au Name of the element(s) or name of the compound(s) the object is made of Picture 1, 2 and 3 are pure substances. What do you think a pure substance is ? How many kinds of elements or compounds do you have ? LIVEWORKSHEETS​