# chemistry AP

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give a scientific explanation for the following observations. Use equations or diagrams if they are relevant.
A. it takes longer to cook an egg until it is hard-boiled in Denver (altitude 1 mile above sea level) than it does in NYC (near sea level).

• chemistry AP - ,

If I had a black board I could draw a picture for you but, alas, no such thing is available.

Here is the explanation. You can supplement with a drawing or two if you need it.
The definition of boiling point (of any liquid but here we are concerned with water) is the temperature at which the vapor pressure of the liquid equala atmospheric pressure. So at sea level, the boiling of water is 100 C because 100 C is the temperature at which the vapor pressure of water equals 760 mm Hg (sea level pressure) on a normal day. So what happens in Denver, the mile high city? Atmospheric pressure is lower than 760, therefore, water boils at a lower temperature than 100 C (say 95 or so). An egg plopped into a kettle of boiling water at sea level will be cooked at 100 C. An egg similarly plopped into a kettle of boiling water at mile high Denver will be cooked at 95 (or whatever the lower temperature is and it would be even lower on the top of those 15,000 ft hills around Denver). So guess why it takes longer to cook at egg in Denver than in New Orleans (or NYC). Simply because we are cooking at a lower temperature in Denver than in NYC.

• chemistry AP - ,

Thanks so much!

• chemistry AP - ,

The boiling point of water is lower than one hundred degrees in denver cuz of high altitude.