1: White gas is made up of small droplets of liquid - water vapor is invisible. When the fire is extinguished, the water cools quickly, forming a large number of small liquid droplets
2: Cover it. pot after cooling with cold water When water vapor cools in water, the pressure decreases. When the pressure decreases, the boiling point decreases, so the water boils.
3: Insurance - When the temperature is too high, the plastic melts, blocks the current and cuts off the power.
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Usually when we boil water, we will know that the water in the kettle is boiling as soon as we notice that steam begins to come out of the kettle spout and the spout squeaks when we blow on it, so we must quickly put out the fire. And in our common sense, the temperature at which water boils is 100°C. If you continue to boil the water, the water in the pot will evaporate quickly.ent.
So if there is enough firepower, can the water be burned above 110℃? If you just increase the firepower, the water will not burn up to 110°C. In fact, we have already noticed this problem in our lives. When a pot of water is boiling, if we continue to turn on the fire, it will continue to boil with heat until the pot of water evaporates. If we insert a thermometer into the water at this time, we will find that the temperature displayed on the thermometer is still 100°C. It will not reach 110℃.
How to boil water above 110℃? The answer is simply to put a little pressure on the water.
We learned in college physics class that the boiling point of water is 100°C under standard atmospheric pressure. Note that there is a condition here which is standard atmospheric pressure. In other words, the fact that the boiling point of water hastteigne 100°C is linked to atmospheric pressure.
So how does atmospheric pressure affect the boiling point of water? At room temperature, water is a liquid. It evaporates when exposed to heat, producing steam. When the steam pressure is equal to the external pressure, the steam pressure will reach a saturation state at this time, and the water will boil at this time. The temperature at which water boils at this time is the boiling point.
If the external pressure increases, the water vapor pressure will also increase. At this time, the temperature must continue to increase for the vapor pressure of the water to reach saturation. The boiling point of water will therefore also increase. Conversely, if the external atmospheric pressure decreases, the boiling point of water will decrease accordingly.
So if we want to boil water above 110℃, just increase the pressuren external. For example, we put water in a pressure cooker and boil it. In this way, water can be boiled above 110℃. The boiling point of water in a pressure cooker can reach 111.6°C.
In high altitude areas, the atmospheric pressure is much lower than in low altitude areas. The boiling point of water at high altitude is therefore less than 100°C. This is why it is not easy to cook rice on the trays. Therefore, if one wants to cook food quickly in the tray areas, it is necessary to use a pressure cooker.