THIS ONE NEEDS TO BE SHARED!!!
Microwaved water - a MUST read
A 26-year old decided to have a cup of coffee. He took a cup of water
and put it in the microwave to heat it up (something that he had done
numerous times before). I am not sure how long he set the timer for,
but
he told me he wanted to bring the water to a boil. When the timer shut
the oven off, he removed the cup from the oven. As he looked into the
cup, he noted that the water was not boiling, but instantly the water
in
the cup "blew up" into his face. The cup remained intact until he threw
it out of his hand but all the water had flown out into his face due to
the build up of energy. His whole face is blistered and he has 1st and
2nd degree burns to his face which may leave scarring. He also may have
lost partial sight in his left eye. While at the hospital, the doctor
who was attending to him stated that this is fairly common occurrence
and water (alone) should never be heated in a microwave oven. If water
is heated in this manner, something should be placed in the cup to
diffuse the energy such as: a wooden stir stick, tea bag, etc. It is
however a much safer choice to boil the water in a tea kettle.
- cynthias's blog
- Login or register to post comments
- 451 reads
For those who has microwave at home, must read.....
For those who has microwave at home, must read.....
that is really scary
Thanks for sharing that.
Dreams Matter.
http://www.associatedcontent.com/user/6562/pchan_stockton.html
For what it's worth ...
... I've boiled water in the microwave, but have always watched for it to boil before shutting off the microwave and slowly removing the cup. I've not heard of this particular kind of accident before, but it's not impossible. Especially in an older microwave without a turntable (which provides some agitation to equalize the distribution of microwave energy and provide for more even, and safer, heating).
I've never bothered
I've always boiled my water for coffee in a kettle - I just didn't like the taste when it was in the microwave - but that is an interesting problem with microwaves. I shall pass the info on.
Wow...
Usually I heat tea in the microwave, which usually involves a tea bag, but I never really thought about why. This just gives me extra reason to make sure I put the bag in before I heat up the water.
Check out my game review blog!
The science behind it.
From http://www.phys.unsw.edu.au/~jw/superheating.html
"Suppose that we heat one kilogram of water from 100 °C (its normal boiling temperature) to 101 °C, i.e. it is now superheated by 1 °C. When it begins to boil, it will very quickly cool to 100 °C, and the heat liberated turns water into steam. Cooling this kg of water by 1 °C gives 4.2 kJ, which is enough to evaporate c/L = 4200/2230000 kg of water. This is only 1.9 millilitres of water, which does not sound very much, but it turns into 3 litres of steam. Those three litres of steam are created insidethe hot water, quite suddenly, so the water is ejected violently from the container."
In other words, the water gets hot enough, quickly enough that bubbles do not appear. The bubbles are necessary, because they use a lot of energy just to form, and help keep the water AT the boiling point without going over, and thus cool the water as it's heating so it doesn't overheat. So when some of these bubbles can form, they get really large, really quickly, and they appear to make the water explode from the cup. The reason this doesn't happen on the stove is because the kettle is getting hot and passing the heat on to the water. But in a microwave, everything is getting hot at once. Anyway, read the site, 'cause they explain it better than I can. lol
But if you want to be like them, you'll have to emulate. -Ayria