Why did some glasses in the past fry when boiling water was poured, but now glasses generally don t

Because the current glass materials are very good, they are all explosion-proof, and they will not fry when poured in boiling water at high temperatures, so they are very safe.

Because the previous glass was ordinary glass, the current glass is tempered glass, which is very resistant to high temperatures, so it will not burst even if hot water is used.

Because the technology of glass making has improved, glass is usually fired at high temperatures, so today's glass is resistant to high temperatures, and even if hot boiling water is poured into it, it will not be fried.

Because the glass has poor thermal conductivity, when boiling water is poured into the glass, the inner layer of the glass expands when heated, and the outer layer is not heated, which will generate outward pressure, which will lead to the glass**.

Because the glass is cold, when pouring hot water, the inner wall will expand and contract, if you slowly pour a small amount of hot water, shake the cup, so that the cup is evenly heated inside and out, you can better avoid bursting.

Because in the cold winter, it will burst when it encounters hot water, which is inseparable from its endurance.

Due to the principle of thermal expansion and cold contraction.

After the glass is filled with hot water, it will expand due to thermal expansion and cold contraction, while after the ruler is put into cold water, the outer wall will shrink due to cold; Previously, the inner wall was still in contact with hot water, and there was no synchronous contraction, and it was still in a state of expansion, and it would be ** under the extrusion of the inner and outer walls.

Since the motion of particles (atoms) in an object changes with temperature, when the temperature rises, the vibration amplitude of the particles increases, causing the object to expand; However, when the temperature drops, the vibration amplitude of the particles decreases, causing the object to shrink. Substances such as water (below 4°C), antimony, bismuth, gallium, and bronze shrink when heated in certain temperature ranges and expand when cold, which is the opposite of the characteristics of ordinary objects.

1 Boil the glass If you want to prevent the new glass from breaking, you can put the newly bought glass in water and boil it for 10 minutes, after the glass is evenly heated, it will not generate strong pressure and will not cause the cup to break. Or you can also put a little hot water to wash the glass before filling it with boiling water, and then pour the hot water so that it will not burst.

2 Put a spoon When pouring boiling water, you can put an iron spoon or a small stainless steel spoon in the cup, and then slowly pour the boiling water into the cup. So that the cup doesn't burst. This is because when boiling water is poured into the bottom of the glass, before it has time to heat the glass (a bad conductor of heat), the boiling water will distribute a part of the heat to the metal spoon of the good conductor, so the temperature of the boiling water decreases, and it changes from boiling water to hot water, which does not interfere with the glass.

As for the boiling water that continues to be poured in, it is not so terrible for the cup, because the cup has already had time to be slightly hot.

3 Avoid using excessive temperature difference Glassware is easy to burst when it is filled with excessively hot or cold water, so avoid using an environment with excessive temperature difference. Usually a temperature difference of more than 80 degrees can cause strong thermal expansion and contraction of the utensils.

It is easy to cause explosions. Unless otherwise specified, try to avoid using utensils with excessively hot or cold water. Before pouring hot water, you can pour a small amount of water, and shake the utensils to make full contact with the hot water to achieve the purpose of preheating the utensils, and then pour hot water to prevent the utensils from bursting due to excessive temperature differences.