Because NH3 boils at −33.34 °C, the liquid must be stored under high pressure or at low temperature. Its heat of vapourization is, however, sufficiently high so that NH3 can be readily handled in ordinary beakers, in a fume hood.
It is cooled before opening its seal to minimise the pressure.
When mixed with oxygen, it burns with a pale yellowish-green flame.Anhydrous ammonia is classified as toxic (T) and dangerous for the environment (N). The gas is flammable (autoignition temperature: 651 °C) and can form explosive mixtures with air (16–25%). The permissible exposure limit (PEL) in the United States is 50 ppm (35 mg/m3), while the IDLH concentration is estimated at 300 ppm. Ammonia reacts violently with the halogens. Nitrogen triiodide, a primary high explosive, is formed when ammonia comes in contact with iodine. Ammonia causes the explosive polymerisation of ethylene oxide. It also forms explosive fulminating compounds with compounds of gold, silver, mercury, germanium or tellurium, and with stibine. Violent reactions have also been reported with acetaldehyde, hypochlorite solutions, potassium ferricyanide and peroxides.