So put a lid on the pan. The air in the pan will heat up as the water heats up, and it circulates back into the water as it's heated. This helps bring the water to degrees F more quickly. And before you know it, that unwatched pot will be boiling. If your pot or pan doesn't have its own cover, look for a universal lid. These lids are designed to provide a snug fit and keep hot air in. For those of us living at sea level, you'll have to suffer knowing that our friends living in parts of Colorado, Utah, New Mexico, and other states with tall mountain ranges can boil water faster by virtue of where they live.
In the higher elevations, the lower air pressure helps water reach boiling in less time. For cities over 10, feet in elevation, the boiling point is a chilly degrees F.
At feet, it's a slightly warmer You can't do anything to impact your city's elevation, obviously. You can just remember this if you ever find yourself cooking in Los Alamos, N. Well Fed program logo.
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Pin FB Share. I never took the time to do the experiment, so I am glad to see this resolved. The pressure release of uncovering could outweigh the lost heat of uncovering. I ran a third trial where I left covered the pot the entire time and timed how long it took to boil by listening carefully to the water as it simmered. It took exactly the same time as when I briefly uncovered the pot to take 1-minute readings. This tells me the pressure did not increase too much.
How well did the lid fit the pot? If it was not completely airtight, then water vapor could escape, so you were not really increasing the pressure inside the pot significantly.
Also, what tgt mentioned below about repeated uncovering. To make water boil at C, you need to have 15psig pressure inside the pot. Thus you need lbs of force to push the lid off. If the lid weighed 1. I think this is being conservative as you are assuming no pressure leaks in the pot-lid seal. Thus, the increased temp rise due to do putting on a lid is small at best and has little effect on boiling time.
Skip to content. My small experiment of boiling water I thought it would be fun to actually boil some water in pots and see how much of a difference covering makes. I used the following experimental design: —I weighed out So here are the results. As explained on this educational website : In the uncovered pot, as the water heats up and gains energy temperature , some of that energy is used to change the phase of the water from liquid to gas.
So next time you need to boil water on the stove, save yourself some time and cover up. I studied Economics and Mathematics at Stanford University. Book ratings are from June Less time cooking equals less used energy. Heat up water in a blemish-free container with minimal disturbance like in the microwave, for example , and because of a lack of nucleation points, it's possible to heat it well beyond its boiling point without it ever boiling.
As soon as some turbulence is introduced—a little wobble from the turntable, for example—bubbles burst forth, sending hot water all over the inside of your microwave. This doesn't happen on the stovetop, since heating from the bottom of the pot creates lots of convection currents the movement that occurs between relatively hot and cool regions of liquid or gas. It's a lot like my wife , who will quietly suppress tiny annoyances until the slightest disturbance will send her into an all-out rage.
In both cases, the results aren't pretty. It's best to avoid these violent outcomes by commenting on how nice your water's hair looks today or by sticking a wooden spoon in your wife before microwaving her.
Here's an interesting one. Say I'm making a stew in the oven. I put my heavy Dutch oven in there, set the temperature to a moderate degrees, and walk away. Eventually, the water should come to a degree boil, right? Actually, no. Because of the cooling effect of evaporation it takes a significant amount of energy for those water molecules to jump from the surface of the liquid—energy that they steal from the liquid itself, cooling it down , an open pot of stew in a degree oven will max out at around degrees.
Good news for you, because that's right in the optimal sub-simmer stewing temperature zone. Pop the lid on, however, and you cut the amount of evaporation that takes place. Less evaporation means higher max temperature.
In my quick test at home, putting on the lid increased temperatures in the pot by almost 25 degrees! For this reason, I generally braise or stew with the lid to my pot slightly ajar. This allows enough evaporation to keep the temperature down, but not so much that the top surface of the stew dehydrates or browns. Pop quiz: I've got two identical pans.
I then add a half ounce of water to each pan and time how long it takes for the water to evaporate. You got it. In fact, when I performed this very test at home, it took nearly ten times as long for the water in the hot pan to vaporize. This seems contrary to pretty much everything we've learned so far, doesn't it? The principal was first observed by Johann Gottlob Leidenfrost, an 18th century German doctor. The epic coolness of his observation is matched only by the epic coolness of his hairdo.
Turns out that if you give a drop of water on a pan enough energy, the steam that it produces will press out so forcefully that it will actually lift the water droplet clear off the surface of the pan. No longer in direct contact with the pan and insulated by this layer of steam, the transfer of energy between the pan and the water becomes quite inefficient, thus the water takes a long time to evaporate. This effect can be quite useful in the kitchen. Drop a bead of water on a pan while heating it.
If, on the other hand, the pan is hot enough for the Leidenfrost effect to kick in, the water will form distinct drops that skid and scoot over the surface of the metal, taking quite a while to evaporate. Congratulations: Your pan is hot enough to cook in. Karen Hill is a freelance writer, editor, and columnist. Hence, the water will reach the boiling point faster.
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