In our daily life, especially when the weather is cold, boiling water poured into the glass may crack and easily cause accidental scald. When the glass suddenly becomes hot under cold conditions, it will expand instantly, resulting in glass burst.
Because the glass expands unevenly, boiling water will break the glass. When hot water enters the cup, the inner and outer walls of the cup cannot be heated at the same time. At first, the inner wall of the cup was heated and the outer wall was in a cooling state, resulting in the rapid expansion of the inner wall while the outer wall remained unchanged. The outer side was strongly pressed by the inner side and broke the glass.
1. Put the iron spoon or stainless steel spoon into the cup, and then slowly pour the boiled water into the cup, so that the cup will not burst. Because when the boiled water is poured into the bottom of the glass, before the glass is scalded, the boiled water will disperse part of the heat onto the metal teaspoon of a good conductor, so the temperature of the boiled water is reduced, from boiled water to hot water, which does not hinder the glass.
2. To prevent the glass from breaking, you can also boil the glass in water for 10 minutes. After heating evenly, there will be no strong pressure and will not cause the glass to crack. Or you can brush the glass with a little hot water first and then fill it with boiling water, and the hot water will not burst.