I’m introducing elements and compounds to my 6th graders soon. One thing I want them to explore is the idea that compounds can have properties very different from the elements that create them.
I have a vague idea of doing a “bad to good” (i.e. reactive sodium plus poisonous chlorine = edible salt) and/or “good to bad” (i.e. carbon plus oxygen = poisonous carbon monoxide) activity, but I’m having trouble thinking of enough examples for my different student groups to research. Anything tied to real-world problems such as pollution is doubly beneficial.
Are there any that you can think of easily? An exhausted and currently brain-dead teacher thanks you in advance!
Well, I wouldn’t try to demonstrate either of the examples you mentioned. One easy one is iron plus oxygen yields iron oxide (rust). You could use plain steel wool from a hardware store or just rinse the soap out of some Brillo pads. Dry the pads after rinsing with a hair dryer. Have the kids examine, describe, etc. the pads before they rust. Have them moisten them with water and leave them overnight (if you want to ensure total rusting, use salt water- inform the kids it’s a catalyst and just helps the oxygen and iron combine faster). Examine and study the next day.
Take a look at primary resources, the number beside the lessons is the year group that the lesson is suitable for. I never use the lessons as they are, but instead use the site for inspiration and help with topics that I’m unsure how to approach.
I would like to join in with California Jobcase is saying stay away from alkali metals without a proper lab and the appropriate safety equipment.
You could demo oxygen and carbon dioxide with candles, jars and water, showing how oxygen in used up. Or, vinegar and sodium bicarbonate to produce carbon dioxide and use it to extinguish a candle.
Sorry, I was unclear…we’re not doing any demos - just researching! This is their first, very basic introduction to elements and compounds, but I wanted them to make some real world connections.
Last year I did show a video of sodium reacting in water, and they all knew chlorine was a poison, so they were amazed that the two together made salt. I wanted to find some similar examples to demonstrate how element properties change as compounds form.
Now, the unit after that is chemical changes - that’s when all the fun experiments happen!
Thanks for the input and the good ideas for hands-on activities (my favorite).
Well the obvious one, surely, is hydrogen + oxygen <—> water. This is good because water is very familiar, and you can point out that oxygen is all around them, in the air.
