Wednesday, 17 July 2013

Science: experimenting with ice!

You know the Ice Marbles we made in winter?  If not you can follow the link to see how to make them at home.  Seeing as it is summer and it is HOT, we thought we'd play about a bit more with it.

and this is what we done...

We got a pot with some watered down food-colouring in; a pot with a different colour of food-colouring in; a pot with a tablespoon of salt and a pot with a tablespoon of baking powder in.

We used hands for the baking powder and the salt and turkey basters for the food colouring then I let them play about, experimenting and exploring and oh the questions that flowed!

Questions were as follows:

What is this white powder?

Is it flour?

When I told them it was baking powder we talked about other experiments we've done with it and asked what would happen on the ice (the hypothesis) and then we tried it...

Why didn't it fizz very much like it does in water?

What will happen when we add some watery food-colouring?

Wow!  It fizzes now!

What does the salt do?

Oh! It feels colder! (Honi exclaims)

They played on and then Honi asks...

Why aren't they melting very quickly?

Good question, the bigger the ball of ice the longer it takes to melt, it's all about surface area.  Also this can lead to questions like:  how hot does ice need to be to melt.

We didn't, but might next time, of course it's something you could try: Get two bowls of water, one hot, one cold which ball of ice do you think will melt first?  Which one actually melts first?

Or you could place one in a metal container in the sun and the other in a plastic container in the sun.  This is a bit like a giant version of the experiment: Insulation and conduction.

Honi's solution to the slow melting process...

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Can I throw it and see what happens?

Of course this leads to other discussions of why the ice breaks like this!

I could go on but now I have more ideas for more posts so I will leave it there.  Have fun playing with your Ice Marbles on a hot day!

For more fun experiments to try check out An Ordinary Life's science page