One spring day
I took advanced higher chemistry (scottish) at secondary school in my final year, along with another bloke in my year. Part of the course is a "research project" and due to much arsing around we were both running quite a bit behind schedule. The school had classes during easter break to help kids out before their big scary exams so we got permission to go into the adv. higher lab and finish our projects. Totally unsupervised.

The first thing that went wrong guess would be the massive white column of fire coming out of the cooking pot - which left a suspicious black mark on the ceiling. Anyone who has played around with oxidising agents may know that there is often a pause between mixing and stuff flaring. An that's exactly what happened here - with a teacher coming in to check on us in the intermittent period.

"Hey guys just wante-" then the extreme whoosh noise.

He was, needless to say, massively impressed. He had just graduated and spent his days teaching twelve year olds that water boiling isn't a chemical reaction. It was time for him to have fun.

And that's how I ended up outside next to said pot filled with various quantities of substances like potassium permanganate and aluminium powder. I was left to "guard it from the weans", because the other two had went back inside for more supplies and a small crowd of kids on bikes had gathered.

No sooner were they in the door than the billows of purple smoke started. The stuff filled this large half-enclosed car park in seconds. Then the whoosh came. Different from before: louder, more purple and not a column of fire, but more of a proper explosion.

If only it was the neds on bikes that got it and not me.
(Phase3Profit pees too much, Fri 13 Feb 2009, 10:32, Reply)