Saturday, 30 November 2013

Out and About in December

This month is busy for us with lots of secondary schools choosing to boost science by booking a show as a Christmas treat plus we have a festive Chemistry at Work day at Daresbury labs with the wonderful team from MerseySTEM and CheshireSTEM
and a Creative Curriculum Conference for student teachers at Manchester Metropolitan University Didsbury campus.

So I have spent the day sorting out our equipment ready for a tour of Merseyside and Cheshire with our show "I wasn't Expecting That!" which highlights some of the fascinating materials out there plus dusting down some of the old chemistry show favourites such as the whoosh bottle, chemical clock reactions and the milk powder flame ball.

There is always way too much to put into a single show and although the temptation is to include everything, we have learnt from experience that we have to carry all this extra around with us so now everything has to earn a place.
Out goes the colourfully named Traffic Lights demonstration using indigo carmine because it is really not reliable for a full day of shows and we often don't have the time or facilities to make up new solutions, whereas the blue and pink bottle both can be depended on to work all day - these are reactions that use dextrose in colour change reactions

Apologies for the music on this video but it shows the demo well

Also in our show will be the now famous hydrogel balls and this time we have made up a rainbow of colours and I have taken photos of the stages
The first photo shows some of the balls in their dried state - they are about 2mm diam actual size

 this image shows a few of the balls after 10 minutes and you can see they have already started to absorb water
after 30 minutes they now have a fuzzy edge and interestingly some  colours seem to be absorbing water faster than others
 after 45 minutes the central core of the balls is becoming quite indistinct the average size is now 6mm diameter

after 1 hour the balls have grown to about 8 mm diameter and have filled the bowl they are in and used up all the water so I added more
 after 3 hours the balls are almost full size and transparent - most will eventually be about 12mm diameter

These smaller balls are easy to buy either through school science suppliers, science toys or from garden centres where they are used by flower arrangers

The large hydrogel spheres we use in our shows are from Mindsets online. They are about 25mm diameter and of course these are the ones that seem to disappear in water. I think perhaps this is my favourite clip of them

So we are on the road next week and hopefully will be able to collect some good images from our adventures - it is always tricky because schools are wary of us taking photos naturally but we will see what we can this space