Chromatography Lesson Plan s1

Chromatography Lesson Plan

Equipment/resources:  Evidence bag containing; threatening note, 3 suspect pens used to write the note, chromatogram of ink from the note  3 suspect pens (labelled A, B & C)  Strips of filter paper x 30  hairdryer  Starter information sheet (Holly Wells & Jessica Chapman)  Plenary activity sheet (Forensics word search) Equipment from lab:  Boiling tubes  Pencils  Water

Lesson Overview

Starter Read through the Holly wells & Jessica Chapman sheet; detailing how forensics caught their killer. Go through questions verbally - on slide 4

Main activity – paper chromatography Set the scene of mock crime & show evidence (physical evidence in evidence bag, details of the crime and suspects on PowerPoint) Detail the technique of paper chromatography: 1. Draw a pencil line across the filter paper about 2cm from the bottom 2. Place a small dot of the ink to be tested in the centre of the line 3. Add a small amount of water to the boiling tube (must not go above the pencil line of the filter paper) 4. carefully place filter paper into boiling tube 5. Allow ink to separate & remove from boiling tube

Chromatograms can be dried with a hair dryer should pupils wish to keep them. Compare the chromatograms of suspect pens to the chromatogram of the ink from the note. Discuss which suspect it could be. Explain the process of separation (detailed in PowerPoint.)

Plenary Discuss key terms involved in forensic science and pupils can complete a word search