Paper pot boiling water question, the principle of paper pot boiling water

This is because the ignition point of paper is generally 183, while the boiling point of water is only 100. When the water is heated in a pot made of smooth paper until the water boils, because the water must continue to absorb heat in the process of boiling, and the water temperature remains unchanged, that is, as long as there is water in the pot, the water temperature will always be 100, that is to say, it will not reach the "ignition point" of the paper, so you can use the paper pot to boil water, the water boils and the paper will not burn out, only when the water in the pot is boiled, the temperature of the pot is 100 because the boiling point of water at room temperature and pressure, and the ignition point of the paper far exceeds the boiling point of water.

When a paper pan is heated, the pan quickly transfers heat to the water inside the pan. When the water heats up, it is until it boils. When the water boils, the heat required for water evaporation is in dynamic equilibrium with the heat generated by the fire.

As a result, the water temperature will not continue to rise. Paper pots, on the other hand, do not burn because they do not reach the ignition point.

Is the analysis very thorough, I remember doing this experiment when I was a child. Today I finally understand the reason.

The heat of the fire is transmitted to the water through the paper.

Yes, at a standard atmospheric pressure, the boiling point of water is 100, and the ignition point of paper is 183, when boiling water, water continues to absorb heat from the paper pot, even after boiling, the temperature of water also keeps the boiling point unchanged, so that the temperature of the paper will not exceed 183. So the paper pot does not boil when the water boils.

It is a physical phenomenon that the paper pot can boil water, the paper contains water, so there will be heat transfer between the paper and the water, and the highest boiling point of water is only 100 degrees, but this temperature does not reach the ignition point of the paper, that is to say, no matter how the paper is burned, it can reach 100 degrees. So the paper pot can be burned.

It's heat conduction.

Why are you so complicated?

Boiling water in a paper pot is a physical experiment. Originated from an experiment in an eighth-grade physics book that asked if the paper had been burned by fire. If water and paper are burned together, the temperature of the paper will not exceed 100 degrees due to heat conduction, because if it is exceeded, the heat is transferred to the water, and the heat is transferred from the low temperature to the high temperature; If you only burn paper, the heat cannot be transferred anywhere else, and the temperature will continue to rise until it burns.

Combustion requires three conditions: the presence of combustibles, contact with oxygen, and the reaching of the ignition point, all of which are indispensable. Although boiling water in a paper pot can come into contact with oxygen and have combustibles, the ignition point is not reached.

Because the temperature of water is 100 degrees Celsius after boiling, and with the evaporation of water vapor, it will also take away some of the heat, which will make the temperature slightly lower than 100 degrees Celsius, and the ignition point of the paper is higher than 100 degrees Celsius, so it will not ignite.

The boiling point of water is 100, the burning point of paper is 170, and when the water boils, its temperature will remain at 100 and will not rise until the water has completely evaporated. In this way, the temperature of the paper will also be kept at 100, far from its burning point, and of course it will not burn. Because the boiling point of water is 100 degrees, and the ignition point of paper is 183 degrees, after the water boils, it continues to absorb heat but the temperature remains the same, and the paper cannot reach its ignition point, of course, it will not be burned!

Because the burning point of paper is 183, it only takes 100 for water to boil. When boiling water in a paper pot, the temperature of the paper will not exceed 100 due to heat conduction. If the temperature on the paper exceeds 100, the heat will be transferred to the water, and as the water vapor evaporates, it will also take away some of the heat.

So the temperature on the paper is always below 100, and that's the process cycle, and the water is finally boiled.

Extended Materials. Boiling water in a paper pot is a physics experiment in an eighth-grade physics book, which can be completed using a smooth thick piece of paper (preferably kraft paper), an alcohol lamp, and an iron stand.

Precautions for experiments: Do not let the flame burn above the water surface of the paper, and use the lamp cover to extinguish it in time after the alcohol lamp is used up.

Because the water in the paper pot can only reach a maximum of 100 degrees Celsius, while the ignition point of the paper is above 400 degrees Celsius, it will not burn because it is heated in a short period of time, and the heat is absorbed by the water.

Hello, at one standard atmosphere, the boiling point of water is 100, while the ignition point of paper is 183When boiling water, the inside of the paper contains water, and there will be heat transfer between the paper and the water, and the water continues to absorb heat from the paper pot, taking away a lot of heat, and the temperature inside cannot reach the ignition point of the paper, so it cannot be burned. Hope it helps.

Because the burning point of the paper is higher than 100, and the maximum temperature of the water is 100, that is, boiling, no matter how much it is heated after that, as long as the water does not dry the paper pot can not reach the burning point, it will not burn.

Because the process of changing water from a liquid state to a gaseous state requires endothermy. The paper pot boiling water is to take advantage of this feature. At a standard atmospheric pressure, the boiling point of water is 100, and the ignition point of paper is 183, when boiling water, the water continuously absorbs heat from the paper pot, even after boiling, the temperature of the water remains the same boiling point, so that the temperature of the paper will not exceed 183.

So the paper pot does not boil when the water boils.

There is also a large heat capacity of water, and it absorbs heat quickly, so the paper pot is put water first (to supplement the upstairs).

The boiling point of water is 100 degrees, and the ignition point of the paper is higher than 100 degrees (I forgot how much), and as long as the temperature of the fire is controlled above 100 degrees, the ignition point of the paper is below it, so that the paper can be boiled without recombustion, and the water can be boiled.

I don't know what I'm asking

There is water in it that comes into contact with the paper, which does not make the temperature of the paper reach the burning point.

Of course, it won't be burned.

The boiling temperature of water is 100 degrees Celsius at a standard atmosphere (approximate to the surface pressure in a plain area), and if the heat transfer between paper and water can be carried out smoothly, then the temperature of the inner surface of the paper will not be higher than 100 degrees Celsius, and the temperature difference between the inner and outer surfaces of the paper will not exceed 10 degrees Celsius (if the paper is not very thick). Therefore, even if the water boils, the temperature of the outer surface of the paper will not exceed 110 degrees Celsius, and the ignition point of the paper is about 130, so it will not cause the paper to burn. Of course, if you don't fold it well enough so that some areas of the paper don't come into full contact with the water, then you might ignite the "small pot".

Note: After the water boils, the temperature does not continue to rise, and I don't think the reason needs to be explained.

I wonder if you're happy with the answer?

There are three elements of combustion.

combustibles, combustible gases and reaching the ignition point.

Because of the presence of water, if the temperature is up to 100 degrees Celsius, the ignition point of the paper may not be hit, so it cannot be burned.

I didn't turn it off, I thought the water temperature was 100 degrees Celsius, and I didn't reach the ignition point of the paper

The ignition point of paper is higher than the boiling point of water, and when the paper pot boils water, the heat is absorbed by the water (heated to maintain boiling), so the paper does not burn.

The boiling point of water is only 100 degrees, while the ignition point of paper is close to 200 degrees, so when the water temperature of the paper pot is only 100 degrees at the maximum, the paper will not burn unless you boil the water dry

The conditions for combustion are: there are combustibles, and the temperature reaches the ignition point of the combustibles, which helps the combustible gas. All three are indispensable.

The paper does not burn because the temperature does not reach the ignition point of the paper (the temperature of the paper is always below 100, and the ignition point of the paper is above 300).

Paper pot boiling water Paper pot will not be ignited because the boiling point of water is not lower than the burning point of paper, so the paper pot will not be ignited when the paper pot is boiling water. i.e. if water and paper are burned together, the temperature of the paper will not exceed 100 due to the conduction of heat;

Because if it is exceeded, the heat is transferred to the water, and the heat is transferred from the place where the temperature is high to the place where the temperature is low; If you only burn the paper, the heat cannot be transferred anywhere else, and the temperature will rise all the way to the ignition point of the paper, causing the paper to burn. And paper burning needs 183, can make water boiling only 100.

Because the process of changing water from a liquid state to a gaseous state requires endothermy. The paper pot boiling water is to take advantage of this feature. At a standard atmospheric pressure, the boiling point of water is 100, and the ignition point of paper is 183, when boiling water, the water continuously absorbs heat from the paper pot, even after boiling, the temperature of the water remains the same boiling point, so that the temperature of the paper will not exceed 183.

So the paper pot does not boil when the water boils.

There is also a large heat capacity of water, and it absorbs heat quickly, so the paper pot is put water first (to supplement the upstairs).

The reason why the paper pot does not boil is because the water needs to absorb heat in the process of changing from liquid to gaseous, the boiling point of water is 100, and the ignition point of paper is 183, and when boiling water, the water continues to absorb heat from the paper pot, even if the temperature of the water is boiled and the boiling point will not change, and the temperature will not reach 183.

The paper pot will not boil the water.

The pot is an essential tool for us to cook and cook, it can be seen in every household, the common pot material is iron, stainless steel, etc., whether it is used to boil water or cook porridge is very convenient, but if you want to boil water, it is also very good to use a paper pot, you only need to add water and then put it on the fire to burn.

However, some people have questions, why can paper be used to boil water when it can be easily lit and burned clean by fire? In fact, this is mainly because water needs to absorb heat in the process of changing from liquid to gaseous, we all know that the boiling point of water is 100, and the ignition point of paper is 183, when boiling water, water constantly absorbs heat from the paper pot.

In this way, even after boiling, the temperature of the water will not change the boiling point, so the temperature of the paper will not reach 183, so that when the water is boiled in a paper pot, it will naturally not boil.

The paper pot boils water, because according to the heat transfer, the temperature of the paper will not exceed 100, and it will not burn if it does not reach the ignition point of the paper. Although the temperature of the flame exceeds the ignition point of the paper, its heat has been transferred to the water, and according to the principle that the heat is transferred from the place where the temperature is high to the place where the temperature is low, it will not burn in the presence of water.

In the absence of water or the water has evaporated, the temperature received by the paper cannot be transferred to other media, and the paper will still burn after the paper ignition point is exceeded.