The bubbles that form before water boils?

Question

You know the little bubbles that form on the bottom of the pot, what are they filled with?

Answer 1

Water vapor.

The bubble at the bottom of the pot are an example of the first stage of boiling - nucleate boiling.

This is a wikipedia article that talks about the stages of boiling:

http://en.wikipedia.org/wiki/Boiling

And here is one that specifically talks about the bubbles you refer to!

http://www.boston.com/news/science/artic...

Hope this helps!

Answer 2

definitely not air

Answer 3

pretty ponies and unicorns!

Answer 4

The imperfections in the pot play a role. I heard on the news of cases where people boil a Pyrex dish full of water in the microwave. The Pyrex is so smooth that in rare cases the water doesn't boil even though the temperature is past 212. They pick up the dish and set it on the counter. When they set it on the counter, it explodes and burns their face and hand. You see, it should have been boiling, but it wasn't, so there was a lot of pressure built up, and when the dish hits the counter, it unleashes the pressure. I guess you are supposed to draw some conclusion from that to help understand boiling water. ^_^

Answer 5

Water vapours.