Last week our Year 3 and 4 students collaborated with our Year 11 and 12 Chemistry class on a few experiments.
Currently, our Year 3 and 4 students are studying a unit of work called ‘What’s the matter?’. In this unit, we look at the changes of state to materials when heat is added or removed and we investigate the properties of matter. The actual outcomes for this work are:
- Identifying that adding or removing heat causes a change of state between solids and liquids.
- Identifying the physical properties of natural and processed materials, and how these properties influence their use.
In class, we have been making predictions about how a material will change its form when we add or remove heat. The students have been designing their own experiments and then conducting them, observing them and reporting on the results, i.e. was their prediction accurate, and why or why not?
My colleague, Dr Darryl Nelson, mentioned that the Year 11 and 12 students are learning about endothermic and exothermic reactions and needed to complete this particular experiment. Both Year 11 and 12 examine changes of state at different times during their courses and need to explain it in terms of the strength of the chemical bonds that hold atoms and molecules together.
We thought it would be a perfect opportunity for the Year 11 and 12 students to explain and model the experiment to our younger cohort. This also provided our younger students with an opportunity to utilise the predictive and reporting skills they have been working on in class.
Of the experiments that were conducted, Dr Nelson said, “We conducted an experiment with iodine. It is a solid, but “boils” at 115oC, so heating in a bunsen burner produces a beautiful purple vapour. This vapour is irritating so the iodine is placed in a sealed bottle. Iodine can be dissolved in ethanol and is an active ingredient in Betadine for wounds. The other experiment was adding two solids to produce a liquid (which was water) and ammonia gas. The reaction is highly endothermic, meaning it requires energy from the surroundings to occur, and it becomes very cold, usually reaching -20oC.”
While the technical nature of the experiment was important for our senior school students to understand and execute, the unique activity of bringing our junior and senior students together to conduct experiments created a positive impact on our younger students and provided another opportunity for our senior students to lead and inspire.
Here are a few words from our Junior School students:
Aiden Moore- “I thought the experiments were really interesting, especially the one where they made the solids become purple gas just by applying heat. It made me really excited to do chemistry in the future.”
Kobi Buechner- “It was so exciting because it was like we were real scientists doing real experiments. Dr Nelson made a volcano and we watched it erupt.”
Helena Smith- “It was cool and fun and also educational! There was lots of suspense while we waited for the explosion!”
Alex Hearn- “I thought the experiments with the Year 11 and 12 students were incredible because we got to see liquids skip the change of state process and go straight to gas!”
Thank you to the Year 11 and 12 students who conducted the experiments and to Dr Nelson for organising such a fantastic learning opportunity.