Chemical and Physical Changes

In this practical, we did loads of heating using the bunsen burner, which is really fun. I like bunsen burners. You get to see both chemical and physical changes of a substance.

What are the differences between a chemical change and a physical change?
The difference is that there is a change in energy (energy taken in or given out) in a chemical change, but not in a physical change. Also, new substances are formed and the process is irreversible. However, no new substances are formed when there is a physical change and that you can still obtain the original state of the substance using other physical means.

Firstly, we heated two different substances: sodium chloride and copper (II) carbonate. The change in the sodium chloride was really really really slow. For my pair, we could not see the change because there wasn't sufficient time for us to see what happens. By right, we should see a clear liquid while melting and a while solid after it is left to cool.

For the copper (II) carbonate, the change was really fast from a green solid to a black solid.

Sodium chloride on the left, copper (II) carbonate on the right.

Heating up the sodium chloride, but nothing happened :(

Copper (II) carbonate after the chemical change.

Next, we heated up a magnesium ribbon. Before the change, it was a silvery-gray metallic strip but after heating, it became white powdery ash. While heating, it actually gave off a really bright white light! So cool! Here's a video of the change, sit back relax and enjoy! :)

Ready for heating! 

Yup that's it for this cool practical! I really enjoying heating all those stuff 8D.