Dennis Stevenson ds122945 at yahoo.com
Thu Oct 21 22:23:16 MDT 2010

Sent: Thursday, October 21, 2010 10:07 AM


Date: Thu, 14 Oct
2010 19:03:15 -0700

>in case you don't know.......
>Science 101b&and NO most of us did NOT know thisb&look, read, and
>>>B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B  
>>>B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B 
B  Microwaving B Water!  
>>>A B 26-year old man decided to have aB cup of
coffee. He took a cup of B water and 
>>>put it in the microwave to heat it up
(something that he B had done numerous 
>>>times before). I am not sure how
long he set theB timer for, but he wanted to 
>>>bring the water to a boil.
When the B timer shut the oven off, he removed the cup 
>>>from the oven. As
heB looked into the cup, he noted that the water was not 
>>>boiling, but
suddenly the water in the cup 'blew up' into his face. The cup 
intact until he threw it out of his hand, but all the B water had flown
>>>out into his face due to the buildup of energy. B His whole face is
blistered and 
>>>he has 1st and 2nd degree burns toB his face which may leave
>>>He also may have lostB partial sight in his left eye.B  While
at the hospital, the 
>>>doctor who was attending to him stated that this is a
fairly common B occurrence 
>>>and water (alone) should never be heated in
aB microwaveB oven. If water is heated 
>>>in this manner, something should be
B placed in the cup to diffuse the energy 
>>>such as a wooden stir B stick,
tea bag, etc.., (nothing metal).
>>>General B Electric's Response:
>>>Thanks for contacting us, I will be happy to assist you. The e-mail
thatB you 
>>>received is correct. B Microwaved water and other liquids do
notB always bubble 
>>>when they reach the boiling point. They can actually
B get superheated and not 
>>>bubble at all. The superheated liquid
willB bubble up out of the cup when it is 
>>>moved or when something like a
spoon or tea bag is put into it. 
>>>To prevent this from B happening and
causing injury,B do not heatB any liquid for 
>>>more thanB two minutes per
cup. After heating, let the cup stand in the microwave 
>>>forB thirty
seconds! before moving it or adding anything into it.
>>>Here is what our
local scienceB teacher had to say on the matter: 'Thanks for the 
B warning. I have seen this happen before. It is caused by a 
>>>B phenomenon
known as super heating. It can occur anytime water isB heated 
>>>andB will
particularly occurB if the vessel that theB water is heated in is new, or
>>>when heating a small amount of water B (less than half a cup).
happens is that theB water heats faster than the vapor bubbles can form. If
>>>the cup is very new then it is unlikely to have small surface scratches
>>>it that provide a place for the bubbles to form. B As theB bubbles
cannot form and 
>>>release some of the heat has built up, theB liquid does
not boil, and the liquid 
>>>continues to heat up well past its boiling point.
>>>What then usually happens is thatB the liquid is bumped or jarred,
which is just 
>>>enough of a shock toB cause the bubbles to rapidly form and
expel the hot liquid. 
>>>The rapid formation of bubbles is also why
aB carbonated beverageB spews B when 
>>>opened after having been B shaken.'
>>>If B you pass this onB B you could very well save someone from a lot of
pain and 
>>>B suffering.   

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