Australia's Science Forum

Wrap it up in newspaper and bin it!!

Does anyone still do this? Had a request from a grade 9 teacher to do this as a demo.

I've had teachers do this as a demo for Year 12 in recent times, but never for any junior groups. I know they do it here, but not sure who for - only been here two weeks. Make sure it is done in a fume cupboard and leave it there overnight with the fan running before handling.

Yes, we still do it here but only as a demo in the fume hood. It is a high risk prac, so our head teacher decides on a case by case basis whether he will approve the class teacher to conduct it or not.

It's demo ONLY and we use small amounts. Done outside and clean up with lots of water and bi carb soda before wrapping up in newspaper and bin it.
Some teachers try to do big but it's not best with the fumes.

I had a teacher who wanted to do this recently. He figured he'd do it outside, if the students stand back a bit then everything will be fine right? He saw sense when he realised the reaction produces sulfur dioxide gas, and delayed it until he was in a lab with a fume hood.

EDIT: haha Mardi, was writing my response at the same time as yours. I'm sure you use smaller amounts than us!

Yes as a demo in the fume hood.

I do ours in a tall beaker inside the fume hood. I think we only use about 20g sugar and about 50ml of sulphuric acid. the trick is to stir vigorously, you will feel the beaker start to heat up. we keep stirring until it is rather warm and then leave it. you will see it start to steam a bit and then it takes off really well

Thanks for the replies people. We took the approach that Mel mentioned, we decided that for this teacher it was a no go.