water is sometimes made safe to drink by boiling. explain why this might not work if you attempt to do it in an open pan on the summit of mt. everest?
2006-08-01 01:26:44 · 12 answers · asked by cyril_2588 2 in Science & Mathematics ➔ Chemistry
How can you hate chemistry? It's the third best field in the world!
Purifying water by boiling works by heat killing the bacteria or whatever other nasties are living in it. Most living things can't survive at temperature above 100 degrees C, or below freezing. Some things buck this trend, but they're quite rare.
If you boil water in a open pan, or on top of a mountain, the pressure is less than if you did it in an enclosed vessel. Following Le Chateliers principle, lower pressure provides less resistance to the water molecules entering the gaseous state (boiling) so less of a driving force (temperature) is needed.
Thus, in your open pan on top of mount everest, the water will boil at a temperature far below 100C, (I think it's around 70) so it doesn't get hot enough to kill the nasties. Also, all your water blows away because it's all steam and you can't catch it.
2006-08-01 01:51:03 · answer #1 · answered by tgypoi 5 · 0⤊ 0⤋
When you boil water, you aren't just killing the germs. You're also filtering out all the junk. How? When you heat the water, it turns in to gas (in it's pure form) and leaves the other elements in the water. When the gas condenses, all it is is pure water. On Mount Everest, the air pressure is really low. This will make water easier to boil, but the gas would have a hard time floating around. Why? Becuase steam (gaseous water) floats in the air becuase it is lighter than air. When there's so little air in the atmosphere, it will have a hard time floating away from the pan. However, the other reason this may not work well is becuase the water will boil so easily (at lower temperatures), that it might not kill the germs.
Remember boiling points are measured at STP (standard temperature and pressure) because both pressure can affect the boiling point.
2006-08-01 08:42:26 · answer #2 · answered by M 4 · 0⤊ 0⤋
When a city has a water contamination problem they issue a boil water order. Boiling water will kill germs. It will drive off any dissolved chemicals that turn to a gas below boiling temperature. On MT Everest where the atmospheric pressure is low because of less atmosphere above you the temperature at which water boils is reduced. It would take longer to cook potatoes. Bacteria would be killed.The general temperatures where bacteria grow is between 40 and 140 degrees F.
2006-08-01 08:51:02 · answer #3 · answered by science teacher 7 · 0⤊ 0⤋
Saw the right answer several times. Fact is that boiling is what happens with the vapor pressure of the fluid exceeds the ambient pressure which on mt. Everest would be very low.
Therefore, the boiling point temperature on mount everest could be too low to kill the bugs.
Without chemistry life itself would be impossible.
2006-08-01 13:37:40 · answer #4 · answered by Roadkill 6 · 0⤊ 0⤋
1.when the pressure in the surface of boiling liquid reaches the atmospheric pressure that temperature is boiling point.
2.when the height increases the pressure decreases.and boiling point also reduces
3.complete sterilization can happen when u heat any thing at 122 degree c for 20 min.(for some spores.)
4.so u might boil the water at say 80 degree in that height and temperature will not increase due to latent heat
5. u can not kill the microbial which can withstand at that temp
2006-08-01 08:49:24 · answer #5 · answered by ramg 2 · 0⤊ 0⤋
On Mount Everest there is lower air pressure from the atmosphere so it will take longer for the water to boil
2006-08-01 08:32:01 · answer #6 · answered by for_schur 1 · 0⤊ 0⤋
pressure, temperature, and phase are all related for matter. boiling occurs when water has enough energy to change to vapor. atmospheric pressure opposes this. where the pressure is lower (mt. everest, for ex.), less energy is needed to boil the water. that means water boils at a lower temperature. the temperature required to boil may not be high enough to kill the germs in the water.
2006-08-01 08:33:32 · answer #7 · answered by Anonymous · 0⤊ 0⤋
Boiling is the rapid vaporization of a liquid, which typically occurs when a liquid is heated to a temperature such that its vapor pressure is above that of the surroundings, such as air pressure. Thus, a liquid may also boil when the pressure of the surrounding atmosphere is sufficiently reduced, such as the use of a vacuum pump or at high altitudes.
I agree with Adam, it may never get hot enough even tho it appears to be boiling.
2006-08-01 08:35:14 · answer #8 · answered by gnomes31 5 · 0⤊ 0⤋
dangerous bacteria will die in high temperature..
in mount everest (high place), pressure is lower and liquid will boil in lower temperature. so we cannot have water of 100*C in mount everest as liquid is only available below its boiling point
and the bacteria can stand the low temperature without being dead!
2006-08-01 08:59:25 · answer #9 · answered by arifin ceper 4 · 0⤊ 0⤋
Because of low air pressure,water will take a long time to boil.
2006-08-01 08:34:17 · answer #10 · answered by akar 4 · 0⤊ 0⤋