N2O is a colorless gas. Its melting point is -90.86 ̊C (-131.548 ̊F), boiling point -88.48 ̊C (-127.264 ̊F). N2O is moderately toxic, serous side effects include neurological disorders such as memory loss.. So called laughing gas, not flammable. As its name, it can cause people feel happy and relaxed by reducing the oxgen level in the blood. It is widely used as an anesthetic, such as in kids dental procedures. When inhaled, the patient remains awake but feel less pain. However, overdose or frequenty use may cause memory loss and brain damage.