Nitrous oxide

Colourless non-flammable greenhouse gas

Nitrous oxide (dinitrogen oxide or dinitrogen monoxide), commonly known as laughing gas or nitrous, among others, is a chemical compound, an oxide of nitrogen with the formula N2O. At room temperature, it is a colourless non-flammable gas, and has a slightly sweet scent and flavour. At elevated temperatures, nitrous oxide is a powerful oxidiser similar to molecular oxygen. Nitrous oxide has significant medical uses, especially in surgery and dentistry, for its anaesthetic and pain-reducing effects, and it is on the World Health Organization's List of Essential Medicines.

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