Saturday, July 5, 2008

Day Five

Saturday and we are checking out solutions... as we learned the other day, solutions are mixtures of two or more substances. Solutions can be unsaturated (not full), saturated (full) or supersaturated (overfull). Heating up solutions allows you to dissolve more solute (stuff being dissolved) into the solvent (stuff it is being dissolved in) then it can normally hold. Today we made supersaturated solutions of Borax. We are going to use our supersaturated solutions of Borax to create "snowflakes". As the hot solutions cool, they can hold less Borax. The Borax "crystalizes" out and sticks to our pipecleaner snowflakes. When we come back to class we should see some really cool stuff!
We also spent time today to investigate the "Wonders of Water". Water is a really unique substance. Besides being a really good solvent for solutions, it also has some really cool properties. Water molecules have REALLY strong bonds. This causes it to have strong COHESION (water clinging to water) and ADHESION (water clinging to other stuff). These properties of water allow us to make water "walk along the string". Water's strong surface tension is responsible for really cool activites like the "magic jar" (ask us to show you when we get home... shhh it is a secret how it works) and the "bubble on the penny". Water also has a really high HEAT CAPACITY. This means that it absorbs and holds on to lots of energy. A property that is really important in the concepts of Earth Science and Weather. Water's heat capacity is so high that we can boil water in a paper cup! We know! We did it!

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