Reversible and irreversible changes

Classify some changes e.g. dissolving as reversible and others e.g. burning as irreversible; recognise that irreversible changes often make new and useful materials and recognise the hazards of burning materials.

See also ‘Grouping and changing materials’, ‘Changing state’ and ‘More about dissolving’

How a extruder works
Watch an online animation showing filtration in industry.

www.industry-animated.org

Video the mixing of materials which react, e.g. bicarbonate of soda and vinegar

Watch chocolate flakes melting under the heat of the lamp. 

Websites

BBC Science Clips	Material World Ch 4 Science Essentials

Online Quizzes teachingandlearningresources.co.uk	IWB Activity ngfl-cymru.org.uk