>> *A 26-year old man decided to have a cup of coffee. He took a cupof>> 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 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>> suddenly the water in the cup 'blew up' into his face. The cup>> remained intact until he threw it out of his hand, but all thewater>> had flown out into his face due to the build up of energy. Hiswhole>> 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 isa>> fairly common occurrence and water (alone) should never be heatedin>> a microwave oven If water is heated in this manner, somethingshould>> be placed in the cup to diffuse the energy such as a wooden stir>> stick, tea bag, etc.., (nothing metal).*>>>>>>>>>> *_General Electric's Response:_*>>>>>>>>>> *Thanks for contacting us, I will be happy to assist you. Thee-mail>> that you received is correct. Microwaved water and other liquidsdo>> not always bubble when they reach the boiling point. They can>> actually get superheated and not bubble at all.. The superheated>> liquid will 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 happening and causing injury, do not heatany>> liquid for more than two minutes per cup After heating, let thecup>> stand in the microwave for thirty seconds before moving it oradding>> anything into it.*>>>>>>>>>> *Here is what our local science teacher had to say on the matter:>> 'Thanks for the microwave warning. I have seen this happen before.>> It is caused by a phenomenon known as super heating. It can occur>> anytime water is heated and will particularly occur if the vessel>> that the water is heated in is new, or when heating a small amount>> of water (less than half a cup).*>>>>>>>>>> *What happens is that the water heats faster than the vaporbubbles>> can form. If the cup is very new then it is unlikely to have small>> surface scratches inside it that provide a place for the bubblesto>> form. As the bubbles cannot form and release some of the heat has>> built up, the liquid does not boil, and the liquid continues toheat>> up well past its boiling point.*>>>>>>>>>> *What then usually happens is that the liquid is bumped or jarred,>> which is just enough of a shock to cause the bubbles to rapidlyform>> and expel the hot liquid. The rapid formation of bubbles is alsowhy>> a carbonated beverage spews when opened after having beenshaken.'*>>>> *_If you pass this on_**_ _**you could very well save someone froma>> lot of pain and suffering.*>>>>
