what happens to the boiling point of the liquid if the pressure of the surrounding is reduced?

Question

in the hill regions usually pressure is low and in the ground the pressure is normal and it takes more time to boil in hill regions than ground region what happens to the boiling point my mam says it reduces i thing it raises
give me the answer

Answer 1

The boiling point is lowered. If there is less pressure exerted on the liquid as it heats up, it is "easier" (i.e. lower temperature/thermal energy required) for the molecules to become a gas and thus escape the vessel.

Water boils at a lower temperature at higher elevations.

Answer 2

Yes, it is true.

I tried an experiment at the Exploratorium, a scence museum in San Francisco. It consisted of a Plexiglas cylinder and a vacuum pump. You could put some water inside the cylinder (it was not hot water) and suck out the air with the vacuum pump. Not much happened at first, but then the water started to boil. There was no heat source, so clearly the boiling was due to reduced air pressure. Then it got more interesting: the act of evaporating ater takes away heat (this is why you sweat in hot weather), so the water, which was at room temperature to begin with, actually began to freeze WHILE IT WAS STILL BOILING. Ever seen freezing boiling water?

Answer 3

The boiling point of water (and anything else) does drop as the altitude gets higher and this is because air-pressure is reduced. In this case your Mam is right.

Because water boils at a lower temperature things take longer to cook and a rough guide is to add 5% to the cooking time for each 300 meters (1000 feet) of altitude.

As a rough rule of thumb for every 300 meters (1000 feet) the boiling point of water falls by 1 degree centigrade (2 degrees Fahrenheit).

On the summit of India's highest mountain - Kanchenjunga, 8598 meters (28,156 feet) - cooking will take about 2 and a half times as long as it would be at ground level and water will boil at about 72 degrees Centigrade.

More info...
http://www.biggreenegg.com/boilingPoint.htm
http://www.csgnetwork.com/h2oboilcalc.html
http://www.hi-tm.com/Documents/Calib-boil.html

Answer 4

If pressure is reduced the boiling piont is reduced, as this way less energy is needed to change the state of the liquid. the pressure acting on the surface of the liquid is low so the liquid molecules can escape easily as gaseous molecules. your techer was right abt it, the only thing that raises is the time to cook food as the water starts evaporating much before 100 degrees so the food will have to be boiled longer

Answer 5

The boiling point will be lowered as the surrounding air pressure reduces.

Answer 6

It drops