00:02
Hi there.
00:03
To answer this question, i want to reference a little experiment or a little demonstration that i do in my classroom.
00:11
And in that demonstration, i add baking soda and vinegar to a beaker.
00:25
And you've probably seen this reaction before.
00:28
You know it bubbles.
00:29
You know it emits bubbles.
00:31
Well, those bubbles are carbon dioxide gas.
00:37
And the cool thing you can do with this at this point is you can take a candle that is burning and you can pour this over the flame.
00:51
Not the liquid, just the gas.
00:53
So you just tip this enough that the gas comes out and you will see that the flame is extinguished.
01:06
The reason for this is because the carbon dioxide is more dense than the air around it.
01:21
So first of all, it stays in the bottom of the beaker.
01:24
Even though it's forming a mixture with the air that was already in the beaker, the carbon dioxide is more dense, so it is down near the bottom, while the air that was originally in that beaker is toward the top.
01:36
So even though we can't see the difference, we really have a heterogeneous mixture.
01:41
And then when we pour this over the flame, the carbon dioxide that is more dense falls over the flame and serves to prevent oxygen from getting to it...