Microwaved tea, WTF just happened?

[Balmoral]

I had about two thirds of a cup of tea that had gone cold, so I gave it a shot in the microwave. It was quite hot afterwards and the mug was hot (but not too hot to hold by the handle). Anyway, I gave it a stir, and the moment the teaspoon went in, the tea in the mug effervesced like crazy, shooting upwards into the air with an explosion like a rocket motor, leaving the mug empty and the kitchen a right old mess.

I've heated loads of beverages up in the microwave before, never seen anything like this before.

Any ideas?

[Morningside]

Have heard it happen before. I am sure there is a name for it. Here is an explaination.
http://www.snopes.com/science/microwave.asp

[Ste1987]

Well, you learn something new every day

[jshell]

Tends to happen most with liquids without any contaminants or particulates. Introduce tea, sugar or a spoon and whoosh!

[Balmoral]

Blimey, thanks folks. I suppose I've been lucky, just a slight scald on my thumb.

[geeks]

This, is, awesome! I am off to play with the microwave

[Zod]

There is usually amongst the warning diagrams on a microwave one of a beaker with a stirrer in it to tell you to put a (non-metallic) stirrer into a beaker of water before boiling it in there. Not that I've ever seen this phenomenon happen.

[HorneyMX5]

They had me at Super Heating".

[Piersman2]

I had it happen to me once years ago in an early microwave. Put a cup of water in, put the timer on for what obviously turned out to be way too long, took the cup out and when I added a spoon of sugar it fecking exploded! Scared the st out of me and I've never over timed water in a microwave since.

[C0ffin D0dger]

Consider it punishment for reheating tea in the microwave. Just make a fresh brew rather than drinking some stuff that is well stewed.

[Balmoral]

Mr Dodger is quite correct

[Morningside]

Yes, maybe re-heating tea in a microwave should be placed in the Council thread.

[Balmoral]

[jshell]

Morningside said:

Yes, maybe having re-heating tea in a microwave should be placed in the Council thread.

I don't often do that...

[Eric Mc]

Was there any sugar in the tea?

[Simpo Two]

Superheating.

Alternatively, given that molecules move about in random directions, maybe they all moved upwards at once

[plunker]

Dirty mugs rule! I feel vindicated.

[Toltec]

Nice, I knew you could super cool water so that a slight disturbance could cause it to solidify into ice almost instantaneously, but did not know it worked the other way too.

[peterperkins]

Microwaved tea (with bag still in) is an excellent laxative if you are a bit bunged up..

[p1stonhead]

https://www.youtube.com/watch?v=1_OXM4mr_i0

Mythbusters did it and confirmed it.