In modern automobiles, nitrous oxide (often just "nitrous" or "nitro" in this context) is sometimes injected into the intake manifold (or just prior to the intake manifold) to increase power: even though the gas itself is not flammable, it delivers more oxygen than atmospheric air by breaking down at elevated temperatures, thus allowing the engine to burn more fuel and air. Additionally, since nitrous oxide is stored as a liquid, the evaporation of liquid nitrous oxide in the intake manifold causes a large drop in intake charge temperature. This results in a smaller, denser charge, and can reduce detonation, as well as increase power available to the engine. Nitrous oxide, also known as dinitrogen oxide or dinitrogen monoxide, is a chemical compound with chemical formula N2O. Under room conditions it is a colourless non-flammable gas, with a pleasant slightly sweet odor. It is commonly known as laughing gas due to the exhilarating effects of inhaling it, and because it can cause spontaneous laughter in some users. It is used in surgery and dentistry for its anaesthetic and analgesic effects. Nitrous oxide is present in the atmosphere where it acts as a powerful greenhouse gas. Properties. Name Dinitrogen oxide. Chemical formula N2O Appearance Colourless gas. For racing purposes, nitrous oxide is usually contained in an aluminium cylinder; available in a variety of sizes ranging from 2.5 lbs to 20 lbs. While retained in the cylinder the nitrous is in a liquid form and held under high pressure. When it is released from the cylinder into the intake tract its physical state changes from a liquid to a gas.