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Ammonium dichromate is the inorganic compound with the formula (NH4)2Cr2O7. In this compound, as in all chromates and dichromates.
A 2115 (OTTO) Ammonium dichromate, 99% Cas 7789-09-5 - used in pyrotechnics and in the early days of photography as well as in lithography, as a source of pure nitrogen in the laboratory, and as a catalyst.