We had the pleasure of welcoming both year 5 classes from Kells Lane into our science department on Monday 5th December to take part in a lesson looking at chemical changes. The students initially watched demonstrations which showed colour change, gas production, smoke and flames. The purple flame produced when glycerol reacted with potassium permanganate was particularly popular, although the smoke produced caused a few wrinkled noses. These demonstrations met two objectives, firstly to show them different examples of chemical changes and secondly to emphasise safety issues before they carried out activities themselves.
Following a brief safety discussion students carried out a mini investigation watching silver crystals grow on a copper Christmas tree, before the main activity of producing hydrogen gas. The students worked sensibly, following instructions which resulted in all groups being able make and test several tubes of hydrogen. The concentration on their faces then subsequent excitement when their tubes of hydrogen elicited a ‘pop’ was a joy to see.
The finale of the session was to set fire to a hydrogen balloon, then fire hydrogen rockets, in the form of bottles with hydrogen and oxygen, across the room. Although I did tell the class I was teaching that they would make loud bangs, none of them anticipated quite how loud, causing a variety of responses from gasps and hands over ears to giggles. One thing was clear, one wasn’t enough and they cheered as each rocket flew across the room. Both classes responded very enthusiastically when asked if they’d enjoyed themselves, which was a particular relief for me, given that my daughter was in the class I taught and had told me I had better make sure it was good!