Rochelle salt

American  

noun

Chemistry, Pharmacology.

1. a colorless or white, water-soluble solid, KNaC 4 H 4 O 6 ⋅4H 2 O, used in silvering mirrors, in the manufacture of Seidlitz powders and baking powder, and in medicine as a laxative.

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Rochelle salt British  

noun

1. a white crystalline double salt, sodium potassium tartrate, used in Seidlitz powder. Formula: KNaC 4 H 4 O 6 .4H 2 O

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Etymology

Origin of Rochelle salt

First recorded in 1745–55; after La Rochelle

Example Sentences

Then combine 1 part of the alkaline Rochelle salt solution, 1 part of copper sulphate, and 4 parts of water.

From School and Home Cooking by Greer, Carlotta Cherryholmes

In another vessel dissolve pure Rochelle salt to the amount of 2.6 w, and make up the solution to the volume v.

From On Laboratory Arts by Threlfall, Richard

“Fehling’s solution” is prepared by dissolving separately 34.639 grammes of copper sulphate, 173 grammes of Rochelle salt, and 71 grammes of caustic soda in water, mixing and making up to 1000 ccs.;

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 2 "Gloss" to "Gordon, Charles George" by Various

The residue from this powder is sodium potassium tartrate, NaKC4H4O6, commonly known as Rochelle salt.

From Human Foods and Their Nutritive Value by Snyder, Harry

This acid, united to the mineral alkali, makes Rochelle salt.

From Heads of Lectures on a Course of Experimental Philosophy: Particularly Including Chemistry by Priestley, Joseph