Green Chemistry & Purification AP Lab #7First, students will design their own experiment to separate two substances using green chemistry principles. Students will also design and perform an experiment to quantitatively measure the weight percent of the mixture. The activity contains enough materials for 15 groups of students as well as a Teacher?s Guide and Student Study Guide Copymasters. Meets Big Idea 3, Investigation 7, Primary Learning Objectives 3. 5 and 3. 3.