Summer Research Program for
Using Chromatography to Identify Unknowns
Lesson 1 - An Introduction to Chromatography
- Objectives: Students will define
chromatography and related terms. They will observe paper
and thin layer chromatography and identify the principles
- Motivation: Ask students: "How many
different colors are in black ink?"
"Does anyone know a way for us to determine this?"
- Demonstrate separating the ink colors using a beaker of
water, felt tip marker, and chromatography paper.
- Explain/describe the process of chromatography using the
demonstration. [9-12 Content Standard E- Understandings about science and
technology] Define solution, solvent, solubility,
and chromatography. [9-12 Content Standard B- Properties of matter] Explain
what is meant by the distance the solvent travels. [9-12 Content Standard B- Motions and forces] Describe how
this process is used in science. Explain that all
substances may not be soluble in water. Therefore,
other solvents are used depending on what solutes are
being dissolved. Give examples: nail polish remover
and acetone; chlorophylls and alcohol.
- Separation of other ink colors may be demonstrated if
Lesson 2 - Experimental Design
- Objectives: Students will use experimental design
sheets and laboratory reference sheets to develop an
experiment using chromatography to identify substances in
an unknown solution. Design worksheets will be evaluated
and critiqued by the teacher. [Teaching Standard B- Focus and support inquiry while
interacting with students] Correction/adjustments
will be made before experiments will be conducted.
- Direct students into teams to design an experiment for
the problem given. The teacher may also want to
have copies of other experiments involving chromatography
for those students who may need help getting started.
- Collect all design worksheets at the end of the period.
Lesson 3 - Identifying Substances in an Unknown Solution
- Objectives: Students will set up and conduct the
experiments they have designed. They will complete
written lab reports including research findings and
- Direct students to collect materials and conduct their
experiment. [9-12 Content Standard A- Design and conduct a scientific
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