As I’ve been very busy this week, and I’ve let myself get bogged down in a short novel of only 165 pages, I’m writing about something else again today…
One of the nicest parts of working as a lab technician in a school is when you get to help the children in the classroom during practicals – I used to work in a senior school and only had rare opportunities to do this. At Christmas I moved over to the prep school, and it’s really fun working with the younger pupils who often need assistance.
We did a great short practical experiment yesterday … getting the iron out of cornflakes. Yes, you did read correctly – most breakfast cereals are fortified with extra iron amongst other vitamins and minerals. If you happen to have a good strong magnet, this is a good example of kitchen chemistry that anyone can do at home with their kids.
· Get a cupful of cornflakes and pulverise them finely. We put them in a Ziploc bag and used a rolling pin.
· Put them into a container (e.g. sandwich box) and add enough hand hot water to make a really watery slurry – about a cupful. You need the grains to expand, go really mushy and disintegrate.
· Cover your magnet with a double layer of clingfilm – make sure you will be able to unwrap it easily.
· Then stir the slurry gently with the magnet for about 5-10 minutes. Try not to touch the bottom of the container.
· Get a sheet of white paper or card and unwrap the magnet so the wet side of the clingfilm is face down on the card. You should see some little black specks – that’s the iron!
· There is just 2.4mg of iron in a 30g bowl of Kellogg’s cornflakes, so don’t expect too much. Interestingly(!) having just been shopping I found that Nestles cereal like Cheerios have more iron, and Tesco own brand has more still.
· One of my scientific friends tells me that with a higher iron cereal you can float a flake on water and drag it round with a magnet … Next time I’m buying I must check that out.
Now enough of school – I’m on half term. YIPPEE!