Wednesday 14 October 2009

Eggs-periments

Wednesday, October 14th, 2009
Teacher had some eggs in class with her today. She had a problem though - she had cooked some eggs and left some raw, and then put them all back into the egg carton together. We had to help her find a way to tell which were raw and which were cooked. We thought of lots of things, including smelling the eggs (didn't work, they all smelled the same), but most involved breaking the eggs, which teacher didn't want to do. Eventually we came up with the idea of spinning the eggs - this was a tereffic idea. When you spin a raw egg, then put your hand gently on it to stop it, then take your hand off the egg starts to spin again. This is like a child in a car crash with no seat belt - when the car stops suddenly, the child keeps going, maybe out the car window. With the cooked egg, when it is stopped, it stays stopped even when the hand is taken away. This is like a child with a seat belt on in the car. When the car stops suddenly, so does the child. The reason this happens is that the inside of a cooked egg is solid, while the inside of a raw egg is quite liquidy. With the eggs still undamaged we decided to try and see what would happen to a raw egg if we leave it overnight in water. Will it change colour? melt? dissolve? What will happen if we leave it overnight in vinegar? Check this site out tomorrow to find out! No one knows the answer (well, teacher might but she's not telling!) Thursday, October 15th, 2009
We had a look at our eggs this morning. The egg on the left is the one that was in water. When we took it out of the water it looked exactly the same as it did yesterday. The egg that was in the vinegar didn't. All the shell had come off. The shell is still hard but the brown colour came off in the tissue. There was even a brown skim floating on the top of the vinegar. Teacher poked at the egg, and said it wasn't ready yet so it has gone back into the vinegar until Monday. What on earth is going to happen to it?

No comments: