What is the method of making ice with saltpeter?

Put the water in a jar, take a bigger container, put the water in the container, then put the jar in the container, and keep adding saltpeter into the container, and the water in the jar becomes ice.

After saltpetre is dissolved in water, it can be reused by cooling crystallization or evaporation crystallization. As for the ratio, it can be tested several times. If it is not frozen, you can gradually increase the amount. It is suggested to replace saltpeter with chemically pure ammonium nitrate sold in chemical reagent shop, and the effect is more obvious.

Principle: The chemical name of saltpeter is called calcium nitrate. When saltpeter is dissolved in water, it will absorb a lot of heat and warm the surrounding water until it freezes.

Extended data:

Nitrate is often used to make black powder, fuse, glass, matches and fireworks, and also used as fertilizer (potash fertilizer and nitrogen fertilizer) and laboratory analysis reagent. It can be prepared by reacting sodium nitrate solution with potassium chloride. Nitrate can be used to prepare peacock green glaze and can also be used as multicolored and pastel pigments. One of the raw materials for making gunpowder.

Nitrate is also called arsenic nitrate, bitter nitrate, flame nitrate, fire nitrate, frost, raw nitrate and Bedi Zhu Xuan. The smell is bitter, cold and non-toxic. Li Shizhen thinks: It should be bitter, bitter, warm and nontoxic.

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