Thread: Why does..

hot water freeze quicker than cold water? when it is in the freezer.

Originally Posted by Roxy121

hot water freeze quicker than cold water? when it is in the freezer.

Wait...what? :?

Sorry if i'm not making much sense, i'll explain it better. When i put a cup with cold water in the freezer it doesn't get frozen quick but when i put a cup of hot water it does the oppisite. I was just wandering why it does that.

Originally Posted by Roxy121

Sorry if i'm not making much sense, i'll explain it better. When i put a cup with cold water in the freezer it doesn't get frozen quick but when i put a cup of hot water it does the oppisite. I was just wandering why it does that.

The wording was fine...I just never knew that. Can't explain how that could be possible. I mean, in order for that to happen, you'd have to be at very low (?) pressures, if I'm reading this cooling curve:

And this phase diagram: correctly. Even then, I can't see how it will jump from a hot state to a cold state faster than how it will jump from a cool state to a cold state.

It is known as the Mpemba effect and supposedly in certain circumstances, water does freeze quicker when it is hot than when it is cold. I was wondering if anyone had seen a plausible explaination for this occurance. It would seem to go against all that we know about the natural world but it is still nevertheless perfectly natural.