Nitrous oxide

January 14, 2013
Image of Nitrous oxide 3D Image of Nitrous oxide

Nitrous oxide (N2O) is called “laughing gas” because it has a euphoric effect when inhaled. It has a mildly sweet odor and taste. N2O was first synthesized by J. Priestley in 1772. In 1800, H. Davy showed that it is an analgesic; its use as a recreational drug began around the same time. N2O was first used as a surgical anesthetic in 1844, and it is still in use today. It is also used as a fuel additive and aerosol propellant.

Only ≈0.3 ppm of N2O is present in the Earth’s atmosphere, but it is such a strong greenhouse gas that it ranks fourth behind water, CO2, and methane as a climate change contributor. N2O should not be confused with nitric oxide (NO) or nitrogen dioxide (NO2).

MOTW update:
July 19, 2021

Nitrous oxide (N2O) is the third-most-emitted climate change contributor, after carbon dioxide and methane, yet little has been done to curtail it. Now, pressure from government agencies and environmental groups is forcing the chemical industry worldwide to install equipment to abate N2O emissions.

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