Turn and face the change

Today we continued our discussion on changes. In the previous lab (separating mixtures) we exclusively looked at physical changes. In today's lab we will look at chemical changes.
First we discussed the differences between physical and chemical changes/properties. Here are the notes from class

Physical properties

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Some key points from the lecture

Does this really need an explanation?

• The difference between a change and a property is a matter of symantics. We will not be asked to distinguish between the two.
• Physical or Chemical properties are characteristic properties that can be used to identify an unknown substance. All you have to do is look them up.
• People often get confused with phase changes. Boiling, melting, etc are physical changes because they do not change the make up of the substance.
• Chemical changes take the original substance and make a new substance(s). The example that was given was gasoline burning in oxygen to form carbon dioxide (CO2) and water (H2O) 

After the lecture on physical/chemical changes, we went over the pre-lab for the chemical reaction lab. We specifically went over the first question about the signs of a chemical reaction

• light emission
• temperature change
• bubbles 
• precipitate formation
• color change

After the pre-lab discussion, we started the lab but had barely enough time to to finish part A. Rachel M will be the next scribe and she will talk about the lab