precipitate : Idioms & Phrases
Red precipitate
(Old. Chem) , mercuric oxide (HgO ) a heavy red crystalline powder obtained by heating mercuric nitrate, or by heating mercury in the air. Prepared in the latter manner, it was theprecipitate per se of the alchemists.
Webster 1913
White precipitate
(Old Chem.) (a) A heavy white amorphous powder (NH2.HgCl ) obtained by adding ammonia to a solution of mercuric chloride or corrosive sublimate; formerly called alsoinfusible white precipitate , and nowamido-mercuric chloride .(b) A white crystalline substance obtained by adding a solution of corrosive sublimate to a solution of sal ammoniac (ammonium chloride); formerly called alsofusible white precipitate .
Webster 1913
Yellow precipitate
(Med. Chem.) , an oxide of mercury which is thrown down as an amorphous yellow powder on adding corrosive sublimate to limewater.