Nope, not a stupid question at all! Most people don't boil water in
the microwave, because if you overheat it you can get hurt.
To boil plain water in a microwave, use a large (4-cup) Pyrex
measuring cup (Pyrex being virtually unkillable in the microwave).
Fill with the desired amount of water, then *stick a chopstick or
wooden skewer in it*. Stir it a bit, leave the chopstick/skewer in
the cup, and heat on high for one minute per cup of water (so 2
minutes for two cups, etc.):
"Take 1 cup water. Heat it in the microwave on high power for 1
minute. (In a 1000 Watt microwave it takes 1 minute to boil 1 cup of
So what's with the stick in the water? Water acts funny when heated
in the microwave - rather than bubble, it can just become superheated,
and not appear to be boiling until you put something into it. By
leaving the chopstick or skewer in there, you're allowing the energy
to be diffused and reducing your risk of injury:
"The FDA has received reports of serious skin burns or scalding
injuries around people's hands and faces as a result of hot water
erupting out of a cup after it had been over-heated in a microwave
oven. Over-heating of water in a cup can result in superheated water
(past its boiling temperature) without appearing to boil.
This type of phenomena occurs if water is heated in a clean cup. If
foreign materials such as instant coffee or sugar are added before
heating, the risk is greatly reduced. If superheating has occurred, a
slight disturbance or movement such as picking up the cup, or pouring
in a spoon full of instant coffee, may result in a violent eruption
with the boiling water exploding out of the cup."
Risk of Burns from Eruptions of Hot Water Overheated in Microwave Ovens
"If you're really worried about this happening to you, follow the
advice and leave some non-metallic object (such as a wooden spoon or
stir stick) in the cup when you boil water in the microwave."
Consumers need to be cautious that water boiled in a microwave oven
can suddenly "explode."
Hope that helps!
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