The Ammonium dichromate with CAS registry number of 7789-09-5 is also called Ammonium bichromate. Its EINECS registry number is 232-143-1. The IUPAC name is diazanium oxido-(oxido(dioxo)chromio)oxy-dioxochromium. In addition, the molecular formula is Cr₂H₈N₂O₇ and the molecular weight is 252.06. It is a kind of bright orange-red crystals and belongs to the classes of Industrial/Fine Chemicals and Inorganics.

Physical properties about this chemical are: (1)#H bond acceptors: 7; (2)#H bond donors: 2; (3)#Freely Rotating Bonds: 2; (4)Polar Surface Area: 117.97 Å²; (5)MonoIsotopic Mass: 251.914174; (6)Topological Polar Surface Area: 126; (7)Heavy Atom Count: 11; (8)Complexity: 194; (9)Covalently-Bonded Unit Count: 3.

Preparation of Ammonium dichromate: it can be prepared by chromium trioxide and ammonia water. This chemical is a kind of exothermic reaction. You should control the adding speed of ammonia water. The pH value of the reaction solution should be controlled between 4 to 5. Then after a series of cooling, crystallization and drying you can get the desired product. The equation is as follows: 2CrO₃ + 2NH₄OH → (NH₄)₂Cr₂O₇ + H₂O.

Uses of Ammonium dichromate: it is used in pyrotechnics and used as a catalyst and a source of pure nitrogen in the laboratory. In addition, it is also used as a mordant for dyeing pigments, in the manufacturing of alizarin, chrome alum, leather tanning and oil purification.

When you are using this chemical, please be cautious about it as the following:
It has risk of explosion by shock, friction, fire or other sources of ignition. And it contact with combustible material may cause fire. It may cause sensitization by inhalation and skin contact. Besides, it has danger of serious damage to health by prolonged exposure through inhalation. And it is very toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment. In addition, it may cause cancer and heritable genetic damage. You should avoid exposure - obtain special instruction before use. During using it, in case of accident or if you feel unwell, seek medical advice immediately (show label where possible). This material and/or its container must be disposed of as hazardous waste. Moreover, you should avoid release to the environment. You can refer to special instructions safety data sheet.

You can still convert the following datas into molecular structure:
(1)SMILES: [O-][Cr](=O)(=O)O[Cr]([O-])(=O)=O.[NH4+].[NH4+]
(2)InChI: InChI=1/2Cr.2H3N.7O/h;;2*1H3;;;;;;;/q;;;;;;;;;2*-1/p+2/rCr2O7.2H3N/c3-1(4,5)9-2(6,7)8;;/h;2*1H3/q-2;;/p+2
(3)InChIKey: JOSWYUNQBRPBDN-RFRSXZKWAS

The toxicity data is as follows: