Ever have an exploding water?

[LadyCook61]

I was heating water in a mug in the microwave and suddenly water exploded out of the mug in the microwave. the mug didn't have metal on it, but I found out that water can do that if the mug is too hot or water is too hot , I forget which. Anyway , from then on, I heat water in a tea kettle.

 

[auntdot]

Believe it is generally the problem of the vessel.

You heat the water to boiling and bubbles of vapor will form in the knicks and crannies in the wall of the mug.

Lots of knicks and crannies, lots of small bubbles. But a mug or vessel with a real smooth surface will not let many bubbles form and the water will become superheated - heated above the boiling point.

Then for whatever reason suddenly a bubble is initiated and all of that superheated water tosses steam into it and bingo the volcano effect.

You can use a lower power on the nuker and it will help prevent that.

 

[David Cottrell]

I couldn'f figure out why either so I'm careful to keep the time short.

 

[Ask-A-Butcher]

I've heard that placing something in the cup of water while nuking...a plastic spoon, stir stix, etc...will prevent it from exploding.

 

[GB]

I've heard that placing something in the cup of water while nuking...a plastic spoon, stir stix, etc...will prevent it from exploding.

Yes that is correct. A toothpick is a good thing to use too. Basically you just want something where the bubbles can form.

The phenomena of water exploding in the microwave is called Super Heated Water.

 

[babetoo]

boom

never had that happen. but was frying chicken livers last night, and they do pop. flew onto my glasses. got if off right away. noticed this morning that we the lens darkened for outdorrs. had streaks of clear where it should have been dark. will check it again and see if it still happens. good thing i need good glasses anyway.

babe

 

[Wart]

"I imagine," adds Barton, "that by keeping the cup still and microwaving for a long time, one could blow the entire contents of the cup into the interior of the microwave as soon as you introduced any nucleation sites. It is this sometimes explosive rate of steam production that means you should take great care when using a microwave oven."

The link contains a link to a video.

 

[YT2095]

using a MW, you`ll make pockets of Super heated water (water that is above 100c) left undisturbed this pocket will eventually dispate it`s heat to the surrounding water, but if you add Any sort of nucleation site, Bubbles of steam will form and you`ll get a cascade reaction.

Think Coke and Mentos, it`s the same thing, only in this case the dissolved gas is CO2.

 

[Wart]

using a MW, you`ll make pockets of Super heated water (water that is above 100c) left undisturbed this pocket will eventually dispate it`s heat to the surrounding water, but if you add Any sort of nucleation site, Bubbles of steam will form and you`ll get a cascade reaction.

And the nucleation site does not need to be a 'solid'.

On several occasions I super heated water in a large glass mug. Upon removing the mug from the microwave I would tilt the mug away from me slightly and give it a light 'rap' on the counter .... Voosh! .... Tap it again and smaller Voosh. Seemed to come from the center or middling areas of the water, I wasn't getting down there to look, I'm ugly enough.

I read a while back there was a theory that liquid water behaves as a solid until an external force moves it. I believe the theory was van der Waals forces formed blocks or masses in a liquid at rest. When water is disturbed the relatively weak forces are overcome and water acts like a liquid again. And that's called liquefaction or, as I like to call it, the ketchup effect.

I'm guessing the van der Waal forces need overcome for water to become self nucleating.

Sounds like a Google search.

 

[Wart]

Forgot to say, I worked at a Power House/ steam plant for a while.

Gave me a new respect for boiling water and steam, especially boiling water under pressure.

I can never look at a pressure cooker the same way again.

 

[jamison_tilne]

Apparently this super heating can go the other way as well. With super cooled water. I had no idea such things really happened, I had only assume it were myth. Here is a youtube video of super heated exploding water. youtube.com/watch?v=ZAqqpDF4bVw

 

[HeatherW]

I've never experienced exploding water, but I did see it happen on an episode of Mythbusters. From their demonstration I can say that I'm glad that I don't have first hand experience with this.

 

[Wart]

Apparently this super heating can go the other way as well. With super cooled water. I had no idea such things really happened, I had only assume it were myth.

Yep, I mean Nope, I remember a film in High School (30 something years ago) where they showed a flowing brook in winter time, ice and snow on the banks, and stating how water in motion can reach temperatures below 32 degrees.

Neat stuff.

 

[YT2095]

indeed, phase transitions of materials in a metastable state are quite fascinating to watch