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Q:
how to made a cubeice whith out bubbles in?
- mary (age 22)
A:
The bubbles in ice cubes are there because air that's dissolved in the
water comes out of solution as the water gets cold. If the bubbles are
surrounded by ice when they form, they get trapped and remain in the
ice cube.
The best way to get rid of air bubbles is to start with water that
doesn't have dissolved air in it. You can boil the water first before
freezing it, or you can just let it sit out for a while. Water sitting
in a jar will have little bubbles of air stuck to the sides after some
hours (let it sit overnight or a few days). But just letting water sit
all by itself won't get all of the air out -- there will still be some
equilibrium amount of air dissolved in the water.
If you really really really want all of the bubbles out, you can
boil the water in a container with a vacuum, so that air does not
redissolve. Or you could freeze the ice very slowly from the bottom up.
That way, the air bubbles can float to the top as they form and not get
trapped under ice. This can be done by putting an ice tray on top of
freezer coolant coils in an environment that's warmer than 0 degrees
Celsius (there may be frost to worry about here, though). The easiest
way to get most of the bubbles out is just to start with water with
most of the dissolved air out, though.
Tom
(published on 10/22/2007)
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