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 Boiling Impossibilities (Posted on 2005-12-06)
You have a glass jar. You pour in water with a pitcher until it is half filled. You then seal the jar with an air-tight lid. (The only other thing in the jar is regular air). Assuming that the water in the jar is not already boiling after attaching the air-tight lid, how do you make the water boil?

boiling: the state in which liquid water is rapidly changing to water vapor (ie, the water is accually bubbling, not just steaming)

For clarification, the water is plain distilled H20. It is not heavy water, water with impurities, etc...

• You cannot transfer or use anything that transfers light, heat, magnetic, electric, or chemical energy into the jar. (and no, shaking the jar till the water friction causes the water to boil does not work)
• You cannot open or break the glass jar.
• The area in the jar cannot increase or decrease. (You can try but the jar will not shrink, grow, or deform in any way)
• You cannot insert anything into the water.
• You must be able to conduct this experiment with easily attainable equipment, chemicals, and other materials. (ie, no radioactive chemicals, no superpowers, no multi-million dollar scientific equipment, you get my drift...)
• (Note: although it is hard for it to succeed, you can conduct this experiment at home and get the water to boil without any special equipment.)

 See The Solution Submitted by Haruki Rating: 3.2000 (10 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
 re(2): Just a guess | Comment 7 of 41 |
(In reply to re: Just a guess by Larry)

insofar as the S4TD solution goes, I don't think so... removing heat from the jar, while having a (possibly) measureable impact on the air pressure and therefore the boiling point, would have a much greater effect on the water termperature, more than enough to compensate for the lower boiling temperature.  Unless the lid is too far away to suck any heat out of the water - though then that (as the jar is half full) would imply a large jar requiring a large change to affect the respectively large volumes of air and water.

As for the superheating method, the text of the problem to me initially defied this solution.  As soon as superheated water is disturbed in any way it will rapidly boil - certainly ytou can't pour superheated water from one vessel to another without this disturbance.  However, the problem doesn't state that you can't heat it after you pour it into the jar, so maybe...

 Posted by Cory Taylor on 2005-12-06 15:45:24

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