First, liquid nitrogen, liquid nitrogen. It is inert, colorless, odorless, non-corrosive, non-flammable and extremely low in temperature. Nitrogen constitutes most of the atmosphere (78.03% by volume and 75.5% by weight). Nitrogen is an inert gas and does not support combustion. A large number of endothermic contacts during vaporization lead to frostbite. Nitrogen accounts for 78% of air.
Second, dry ice is solid carbon dioxide, which is formed by condensing carbon dioxide into colorless liquid under the pressure of 6250.5498 kPa, and then rapidly solidifying under low pressure. The temperature of dry ice is much lower than that of water, so it is equivalent to heating dry ice, which absorbs heat and sublimates, reducing the temperature of water and even freezing it.
1. Remember to be careful and use thick cotton gloves or other shelter every time you touch dry ice! If it is in direct contact with the skin for a long time, it may cause cell freezing and similar slight or extremely serious frostbite damage. Dry ice cannot be used in sealed places such as cars and cabins, because the sublimated carbon dioxide will be denser than oxygen, so it will squeeze out oxygen, which may lead to shortness of breath or even suffocation!
2. Skin contact with liquid nitrogen can cause frostbite. If there is too much nitrogen produced by vaporization under normal pressure, the partial pressure of oxygen in the air will decrease, and in extreme cases, it will cause hypoxia and suffocation.
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