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Show How Ice Instead of Heat Will Boil Water WATER can be x.ade to boll by cooling the vessel In wh cb it is contained with cold water or Ice, says the Popular Science Monthly. H lo prove this, half fill a thin glass flask with water and Insert a tube In tho neck. Then bold the flask over a burner until tne water bolls. While the steam Is Issuing from the tube, r-move r-move the flask and quickly make airtight with a ; pinch-clamp. . ! The flask may then be set asldo until It has become be-come merely tepid. If you let cold water run Over the flak. the ater within Immediately begins be-gins to boil aain. The colder tho water applied J the greater '.he violence of the boiling. it The explanation ll?s in the fact that the tern- I Hr how yu can Cvjfc work tho OKporimont ijBL 1 of boillnf wator by fiSaSm - I coollnt fth implo aBSMBa I apparatus 0K9H H ocAistuet Ivi I 1 , CONTIrfueO TTDf I OWNO WATER I perature at which water bolls depends upon at- I mo3pheric pressure. When the flask is placed 1 over the flame, part of the water is changed to steam, which expels the air from the vessel As the volume of steam is 3700 times greater than Its corresponding unit of water, the condensation of the steam in the sealed flask reduces the vapor pressure. The pressure of tho steam in the flask ! prevents the boiling of the wnter after the equilibrium equi-librium has teen reached. When the cold water or ice causes further condensation of the steam, the pressure is reduced and the water boils, pro- 1 ducing enough steam to restore tho disturbed balance of pressure |