The use of dichromate compounds in photography and litography is the result of its light-sensitive properties. The dichromate compounds have also the property of hardening onto paper the pigment that is mixed in arabic gum. The gum bichromate prints have a large variety of colors print and the stability and toughness of the gum bichromate prints is not at all neglectable.
The saturation of n% of ammonium dichromate can be obtained by adding n grams of ammonium dichromate into 100 ml of warm distilled water.
You may obtain ammonium dichromate from the following chemical reaction, such that:
`Na_2Cr_2O_7 + (NH_4)_2SO_4 -> (NH_4)_2Cr_2O_7 + Na_2SO_4`