Our Super Science Experiment learning all about dissolving continued this week when we repeated the experiment but this time used hotter water (rather than cold water like we did the first time) and also varied the quantities of substances added to the cups.
First off we checked out our results from the first part of the experiment to see how much of the substances had dissolved or settled in the base of the cups overnight...
We then added each of the substances (artificial sweetener, salt, chicken salt, pepper, curry powder, coffee mix, hot chocolate, ground nutmeg, ground cinnamon and sesame seeds) to the cups of hot water (which Mrs Gorrie had already poured for us and we were careful not to handle - safety first!) :)
We gave each experiment cup a good stir and watched what happened to the substances, whether they dissolved or not...
We found that many of the substances dissolved better in hot water than in cold. We discussed why this could be and there were some very interesting ideas expressed from our amazing 2G scientists...
We concluded that some substances dissolve more in hot water because the heat of the water breaks them down more, mixing them in more easily.
One surprising result that we found was that even though the sesame seeds didn't dissolve in hot or cold water, they turned a darker colour in the cup of hot water. We concluded that the hot water must have cooked them slightly, therefore making them a bit darker.
It was also interesting that our scientists observed that when they were stirring the cups the second time around that the wooden paddle pop stick stirrers felt slightly sticky or 'rubbery' in the base of their cup, so we talked about how this could be tiny particles of the plastic cup disintegrating or it could be because of the heat expanding the wood. This lead into a terrific discussion!
In the recent very hot weather, we noticed that our classroom door was tricky to open and close as it was getting stuck slightly on the door jam surround because the heat had made the wooden door expand. It was wonderful to connect our thinking back to that concept. Science really is all around us!
Well done on your amazing participation in this class experiment 2G! Keep up the terrific thinking and questioning. It's so wonderful seeing your brains working hard as you explore scientific concepts and make discoveries. Way to go champions!