Eggs are amazing! Today we investigated the principles of OSMOSIS and DIFFUSION so that we can better understand what is happening in more experiments we have planned. Did you know eggs have a membrane inside the shell?
This membrane allows some substances to pass through while keeping other substances out. This is called osmosis. We experimented with this idea by mixing salt and lentils and then passing them through a sieve to simulate the membrane. Only the tiny particles of salt were able to pass through the sieve.
Next we looked at diffusion. We put a couple of drops of food colouring into a glass of water and watched. When first dropped into the water, the part of the water that shows colour has a high concentration of food colouring. Over time, the colour begins to spread throughout the water to areas with no colour (low concentration of food colouring). Eventually, the colour is evenly spread throughout the entire glass of water.
We all know eggs are very fragile, right? Today we did an experiment to see just how easily they break. First we emptied the egg and cleaned out the shell. We drew a line aroung the egg and then broke the shell off down to the line. We had to be extremely careful because the shell was very easy to break. Once we had four eggshells ready we placed them on the tray and started loading books on top of them! We were pretty sure they would break but we had THIRTEEN books stacked on top of the eggshells before the first one cracked. Eggshells were much stronger than we realised so the wee chicks inside are kept safe. We also found some building structures that use domes and arches to give them strength.
The JEM's (Junior Extension Maths) have been puzzling over Teddy Town for a while and today Camryn found a solution. What great perseverance she showed to solve this problem. Great work Camryn. Here is her solution.