00:01
Two types of changes to be familiar with are physical and chemical.
00:12
And a physical change is one in which the identity of the substance doesn't change.
00:29
It stays the same substance.
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However, in a chemical change, the identity of the substance does change.
00:42
It becomes a different substance.
00:47
So if we were to look at a match burning, well, when a match burns, it turns that wood and that phosphorus into carbon dioxide and water, it becomes different things.
01:03
So that's going to be chemical.
01:07
If we were talking about a metal gets warmer, well, the metal is still the metal.
01:15
The only thing that's changed is its temperature, but it's still the metal...