HOW SCIENCE WORKS

Methods of Analysis and Detection

Simon Coates – Bristol Grammar School

How Science Works• New program of study for science

implemented in September 2006• Pupils learn about the way science

and scientists work within society• Greater emphasis on the

processes and implications of science and scientific enquiry

The Brief

Design lesson material for the new GCSE specification, with particular emphasis on ‘How

Science Works’.

Problem Topics

• Alternative fuels• Smart Materials and Nanomaterials• Catalysis in industry• Water Hardness and Quality• Instrumental Analysis

New additions to the AQA specification to be considered:

Specification“To evaluate the advantages and disadvantages of instrumental methods and the features that influence that development...the rapid progress in technologies such as electronic and computing”

“To interpret and evaluate the results of instrumental analyses carried out to identify elements and compounds for forensic, health and environmental purposes”

“Some instrumental methods are suited to identifying elements...others are suited to identifying compounds”

AQA GCSE Chemistry Specification

Requirements• A method of analysing elements• A method of analysing compounds• List the advantages and

disadvantages of each method• Give examples of where these

methods are used to solve particular problems.

The Lesson Plan

The Tasks

1.Theory and Discussion – powerpoint2.Analysing compounds – preparing,

running and analysing an infrared spectrum of Aspirin

3.Analysing elements – the emission spectrum of a sodium lamp

4.How Science Works – IR spectroscopy and drugs testing

The Theory• Analysing elements• Analysing

compounds• Atomic Emission Spectroscopy• Infrared

Spectroscopy• Development• Advantages• Disadvantages• Applications

Analysing Elements

Analysing Compounds

Emission Spectroscopy• Emission spectrum of a

sodium lamp• Analytical questions based

on: - steel manufacture - detecting elements in stars

• Activity cancelled due to - lack of time - poor quality spectroscopes - better success with IR

activities

Aspirin• Pupils to prepare a sample of

Aspirin, and run an IR spectrum of their sample

• Pupils then interpret their spectra

• Very time consuming

• Instead, class demonstration and discussion of use of the IR machine

Aspirin

Pupils asked to interpret the IR spectrum of Aspirin based on simple functional groups

Drugs Testing• Application of Infrared Spectroscopy, links to ‘How Science Works’

• Discussion of Drugs testing, based on the upcoming Olympic games

• Applications, limitations and issues of drugs testing in sport

• Analysis of IR spectra of ‘blood samples’

Drugs Testing

Further Work

• Modifications of this lesson to cater for different abilities• Ensure lesson material is suitable across all examination bodies • Extra practical uses of the infrared machine

Acknowledgements

• Mr Tim Harrison• Dr David Smith • Mr Steve Croker• Staff, technicians and pupils at BGS• Dr Jon Stone – school supervisor• Fellow UAS students