chrome alum

American  

[krohm al-uhm] / ˈkroʊm ˈæl əm /

noun

1. Also called ammonium chrome alum;.  Also called ammonium chromic sulfate.  a green, crystalline, water-soluble powder, chromium ammonium sulfate, CrNH 4 (SO4 ) 2 ⋅12H 2 O, used chiefly as a mordant in dyeing.

2. a violet, crystalline, water-soluble powder, potassium chromium sulfate, CrK(SO4 ) 2 ⋅12H 2 O, used chiefly as a mordant in dyeing.

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chrome alum British  

noun

1. a violet-red crystalline substance, used as a mordant in dyeing. Formula: KCr(SO 4 ) 2 .12H 2 O

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Example Sentences

Then write or draw upon it with an ink containing chrome alum, allow it to dry exposed to light, and immerse the plate in water.

From Paper and Printing Recipes A Handy Volume of Practical Recipes, Concerning the Every-Day Business of Stationers, Printers, Binders, and the Kindred Trades by Ford, J. Sawtelle

Both chrome alum and alum crystals are used for the same purpose in photography, for clearing and hardening the film of the negative.

From Harper's Round Table, August 13, 1895 by Various

By adding sodium phosphate to an excess of chrome alum the violet phosphate, CrPO4�6H2O, is precipitated; on heating to 100� C. it loses water and turns green.

From Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 3 "Chitral" to "Cincinnati" by Various

What is the difference between chrome alum and alum crystals.

From Harper's Round Table, August 13, 1895 by Various

The mixture should be employed immediately after adding the chrome alum.

From Photographic Reproduction Processes by Duchochois, Peter C.