05 March 2008

Remember that yucky-tasting salty water?

Do you remember when we dissolved salt in some water? And how Patricia (brave, brave Patricia) tested that yucky-tasting salty water? And how we were wondering where the salt had gone to?

Well, we decided to try to see if we could get the salt back out of the water again.

We poured the yucky-tasting salty water into a saucer and left it by the window, where it was nice and warm. Joe thought the water might start to disappear or 'evaporate' (which Dangi told us means turn to water vapour).

This morning, when we looked at the saucer, this is what we saw:



There was less water (which means that Dangi and Joe must have been right!) and there were also white crystals. When we looked closely at the crystals, we saw different shapes. Some were square with a cross in the middle.

We decided to keep an eye on it over the next few days to see if anything else changed.
By Friday, all the water had evaporated.



A closer look reveals many cube-shaped crystals


Azri had a go at growing some of his own salt crystals. This is what he did:
He stirred salt into water until it dissappeared (or dissolved). Then he tied a piece of string onto a pencil and dangled it into the clear salty water. He left it in a warm place - and waited to see what happened.

He brought it in to show us.

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