This blog post is a first of many, I hope, in the field of dangerous chemicals. Here are a collection of my favourite little nasties I won’t work with in the lab. Today we’ll start of with a “simple” Cadmium compound and tomorrow we’ll look at something that explodes for absolutely no reason at all.
Ready? Let’s kick off with DIMETHYLCADMIUM!
Everyone knows about Lead and Arsenic etc. Did you also know that Cadmium is just as bloomin’ nasty?
I know, as an element, it looks so harmless – but don’t be fooled!. It has acute toxic effects (chemistry’s version of stabbing you – quick acting), and it has chronic toxic effects (ruins you long term).
A Wall of Flame
Lucifer running for a jar of Dimethyl Cadmium Image courtesy of 123RF -(Licensed to Creative Commons)
Dimethyl Cadmium would be the stuff that Lucifer uses to start a bonfire. It’s basically the demon compound of the organometallic world. An organometallic compound is a compound where carbon and metal are bonded together, largely through covalent bonds.
From the drawing above (Image courtesy of SAFC Global), the yellow atom is a Cadmium atom single-bonded to two other molecules. Each molecule is a methyl compound. A methyl compound is highly reactive and is formed of a central carbon atom (grey) and three hydrogen (white) atoms. This particular nasty is referred to as a methyl organometallic compound.
Methyl organmetallics are where you start looking for the most choking vapors, brighest flames, and fondest collection of curse words to ever come out of a chemistry lab. Methyl organometallics are small, highly reactive, and ready to start a party! Dimethyl cadmium is the little demon wedged in this fun collection of man-made nasties.
Spill the stuff and it’ll spread into a nice, wide, pool over your lab – and, of course, it will ignite on it’s own. I cant think of much that would ignite at room temperature but there you go.
What happens once you’ve got a warm fire going in your lab? We all then get to sniff some poisonous cadmium oxide smoke. It’s toxic to your lungs, liver and kidneys. Only a few micrograms per cubic meter are needed and that vapour gets absorbed really well into your blood stream. Cadmium compounds are carcinogenic – so assuming you survive all that chances are you’ll pick up a tumour somewhere down the road.
If that doesn’t happen – I’ll wager you’ll still regret you opened the bottle.
It can react with oxygen to form a thick crust of dimethyl cadmium peroxide – a friction sensitive explosive. This means that if you try and move it it blows up. I still don’t know exactly how you clean that up without blowing yourself up.
Some kids playing with dimethyl cadmium
Image credit :http://static2.businessinsider.com/image/50d0cac869bedd800e000034-480/party-fire-devil-dancing-club.jpg
Any attempt to clean up the explosive will either a) blow you up or b) distribute the rest of your delicious dimethyl cadmium into a fine mist. Inhaling it will give you some nasty surprises. Don’t use water either – just remember that science lesson you had about throwing sodium into water. Something similarly fun may happen.
So in summary this chemical is no longer popular (gee whiz – I wonder why?) with chemists. It is still used in exotic areas of chemistry in developing “exciting” photosensitive and semiconducting materials (Again, not the kind of job you want).
So no, no one loves this chemical – which is why you’ve never heard of it. Play with it in your own time but keep it out of my ‘hood*.
*Pun of the word ‘neighbourhood’ and ‘fume hood’ 😉