Ammonium nitrate is a chemical compound with the formula NH4NO3. It is composed of nitric acid and salt of ammonia. In room temperature, ammonium nitrate appears in a white crystal and it is also colorless. Its melting point is at 169.6 degrees Celsius or 337.3 degrees Fahrenheit.
These crystals are rhombohedral in shape but when they are subjected to temperatures above 32 degrees Celsius, they change to monoclinic crystals.