Chemistry KS3/4: Experiments with air
Three students try out hands-on experiments with carbon dioxide in a science lab.
With the help of Dr Peter Wothers at the University of Cambridge, they explore the properties of the air around us.
They measure the density of carbon dioxide, they create ‘dry ice’ by extracting carbon dioxide from calcium carbonate, and they explore how limewater is made.
Students could be asked to write down word and symbol equations for the processes occurring in this clip.
They could also be challenged to criticise the on-screen graphics and the use of the = sign.
Symbol equations can be balanced.
The thermal decomposition of calcium carbonate can be repeated by students in the lab, using large marble chips on the edge of a piece of gauze and heating for ten minutes with a hot Bunsen flame.
During this time, the teacher can circulate with a butane brûlée torch and heat each chip for one minute until limelight is seen.
After cooling, the chips can be reacted with water and tested using universal indicator drops.
This topic appears in OCR, Edexcel, AQA, WJEC KS3, KS4 and GCSE in England and Wales, CCEA GCSE in Northern Ireland.