is telling to decrease the heat applied once the water boils during boiling soup, a good advice? Why, why not?
156813
the water maintains its tempreture when it has reached boling, so if you reduce the heat it will still be at boiling tempreture (100 degrees centigrade) but it will simmer slowly, so the contents of the soup will be cooked without the water drying out
474034
It decreases, as everyone said. The reason may be given like this: water at a given temperature is just a bunch of molecules wildly moving around. The temperature tells you just how fast. Evaporation (water drying up) happens because some of the fastest molecules escape into the surrounding air. Now, evaporation happens faster at higher altitude: that is because there is less air, the air molecules are less bunched together. This means a water molecule escaping into air is less likely to be bounced right back into the water. \n\nNow boiling occurs when evaporation is so violent that the water cannot hold itself together any more. Again, it will happen more easily in thin air, that is, at high altitudes.
81100
THATS FALSE, ONE SHOULD FILL IT WHEN ONLY HOT. DUH.
297542
well lets see, if cold water is anything above 0 Centigrade and hot water is anything under boiling....my money is on the hot winning. What I can not understand is why you asked?
1052162
On paper that has to be the answer but there is a concept of heat loss when boiling water comes in contact with cold water.\nThe loss is in the nature of steam. \nSteam is at a the temperature of boiling water. \nSo there is a loss of heat. The cold water ends up being less in quantity due to steam loss. \nSo the cold water cannot offset the heat of the boiling water, so the temperture will be higher than that of 50 Degrees.
986563
all right... so here's the deal.\n\naccording to the local health department (i'm quite sure this is a standard), any food that hits the floor becomes trash.  there is no 5 second rule.\n\nadditionally, bacteria isn't the only thing on the ground.  perhaps there is dirt, and fire doesn't kill dirt.  dirt may be sterile, but it's still gross.\n\nimportantly, let's imagine that there is a chemical on the ground, like a cleanser.  that won't cook off either.  and that is poison.  \n\ncooking food to high enough temperatures will indeed kill bacteria, but here is another myth debunked.\n\nsuppose you leave some food out at room temperature for 12 hours, then you cook it up to boiling.  you kill all the bacteria, right?  right, you will kill all the bacteria.  so the food is safe to eat, right?  wrong.  bacteria produce biproducts which are poisonous, deadly even, and these chemicals are in fact dead already and heat does not necessarily destroy them.\n\nso heat is not a cure all for food, and the 5 second rule is crap.
800425
Yes. Boiling temperature depends on pressure. Therefore lowering the pressure below 760 mm (Hg) will lower the boiling temperature.\nAt about 2000 meters altitude, the pressure goes down to about 560 mm and the boiling temperature down to around 93 ºC. \nAt more than 4000 meters of altitude, you can not get a good hot coffee!  The water boils and is just warm.
282621
When I was a little girl I used to get boils often. My mother would get a washcloth and soak it in very hot water then cover the boil. She would do that several times. That seemed to make it go away. It would shrink under the heat.
676099
Heat the substance and once u see steam, wa lah u got a boiling point... don't forgot the thermometer.
571405
?!?!?! Make a hot bowl of boiling water then stick ur head over it 4 a few minutes!
677623
False\n\nWhen steam is cooled to water, both can be 100 degrees C, but steam must give off energy to become a liquid.  The opposite is easier to understand.  When you are boiling water, the steam that escapes will be 100 degrees C, but will have much more energy than the 100 degree water.\n\nIn both of these cases, the energy put into or taken out of the water is used to change its phase, without changing its temperature.
165249
Definitely. After all, water vapor is just the gaseous form of water, and you can heat that quite a bit more. \n\nHowever, I presume you are referring to the liquid form of water. The previous answer is definitely correct. All one has to do is increase the pressure and the liquid water will stop boiling and get hotter.
734492
Heat = mass x specific heat of material x change of temperature.\nSpecific heat of water is 1. So the amount of heat needed to be added is the mass of the water x the amount of change needed to get to boiling. So cold water does not boil faster. \n\nsalt will cause it to take longer. \n\nPeople think that tea tastes betterr if you start with cold water, which holds more oxygen. As you heat the water, the oxygen comes out. This may look like boiling.
232411
Salt only helps the boiling point rise a little. It will boil more rapidly. It will not decrease time it takes to reach boiling point.
875385
Lol, sure as long as your argument is that it didn't say put the soup in boiling water for ten minutes.. If it just said, stand in boiling water ... then ,sure, why not? It might be a lost cause though..\n\n\nGood Luck With That, Though!
77192
No, adding salt does not make water boil more quickly. The colligative properties of water talk about freezing point depression and boiling point elevation. Water will reach a higher temperature before it boils when it contains salt (or any other dissolved substance).\n\nNucleation is a reasonable point, though. In reality, it's probably going to be hard to detect much of a difference. If you're cooking at high altitudes and you add salt to try to make the water boil faster, you're working against yourself.
79685
No.  There was a time when people said it did because some dude in Africa was making ice cream and claimed that his ice cream froze faster if he heated it first, but that's because ice cream needs to congeal, and heating it boiled off much of the water, making it thicker to begin with.\n\nAnd it has been shown even since the time of the Greeks that water that has been boiled prior to freezing will freeze quicker due to the fact that boiling will remove dissolved gases from the liquid, but even that assumes you are comparing water that's been boiled and brought down to temperature versus water that has not been boiled.\n\nBut if you put water that's 8 degrees and water thats 80 degrees in a freezer, the 80 degree water, prior to freezing, will need to reach 8 degrees somewhere between here and there.  All the while, the 8 degree water has made substantial progress towards freezing.\n\nIt is true that hot water loses heat more quickly due to an increased driving force for heat loss, but this is a temporary thing.  As soon as the hotter water reaching the starting temperature of the cooler water, it has no "momentum" in losing heat, but it has lost a lot of time.