gallic acid

Definitions

  • WordNet 3.6
    • n gallic acid a colorless crystalline acid obtained from tannin
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Webster's Revised Unabridged Dictionary
    • Gallic acid (Chem) an organic acid, very widely distributed in the vegetable kingdom, being found in the free state in galls, tea, etc., and produced artificially. It is a white, crystalline substance, C6H2(HO)3.CO2H, with an astringent taste, and is a strong reducing agent, as employed in photography. It is usually prepared from tannin, and both give a dark color with iron salts, forming tannate and gallate of iron, which are the essential ingredients of common black ink.
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Chambers's Twentieth Century Dictionary
    • Gallic acid a crystalline substance obtained from gall-nuts, and used in making ink
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Etymology

Chambers's Twentieth Century Dictionary
Fr. galle—L. galla, oak-apple.

Usage

In literature:

Oxalic, citric, tartaric, succinic, malic, gallic and tannic are other well-known organic acids.
"The Farm That Won't Wear Out" by Cyril G. Hopkins
Ointment of gallic acid and calomel is of repute.
"Searchlights on Health" by B. G. Jefferis and J. L. Nichols
Nut-galls contain a large quantity of tannin and gallic acid, and are extensively used in dyeing.
"French Polishing and Enamelling" by Richard Bitmead
Ergot, in teaspoonful doses of the fluid extract, hamamelis, and gallic acid, all are valuable for this purpose.
"The People's Common Sense Medical Adviser in Plain English" by R. V. Pierce
Ointment of gallic acid and calomel is of repute.
"Searchlights on Health: Light on Dark Corners" by B.G. Jefferis
Dissolve the gallic acid, sesgurichloride, and add the acetic acid.
"The Ladies Book of Useful Information" by Anonymous
True; and that is, perhaps, the reason that a silver knife is preferred to cut fruits; the gallic acid, I suppose, does not act upon silver.
"Conversations on Chemistry, V. 1-2" by Jane Marcet
A weak solution of iodide of iron has also the same effect, and, if blotted off at once, it will not blacken by the use of gallic acid.
"Notes and Queries, Number 203, September 17, 1853" by Various
Inky black colour or precipitate = gallic acid or tannic acid.
"The Elements of Bacteriological Technique" by John William Henry Eyre
A drench of 1-1/2 drams of gallic acid dissolved in a pint of water should be given.
"Special Report on Diseases of Cattle" by U.S. Department of Agriculture
If the weather is warm, 6 drops of gallic acid to the 10 of aceto-nitrate will suffice, and enable the prepared excited paper to be kept longer.
"Notes and Queries, Number 216, December 17, 1853" by Various
I add only, if I have any dissolved, 1 or 2 grammes of camphorated spirits to 1 litre of the solution of gallic acid.
"Notes and Queries, Number 234, April 22, 1854" by Various
Lactate of iron, 15 grains; powdered gum arabic, 75 grains; powdered sugar, half a drachm; gallic acid, 9 grains; hot water, 3 ounces.
"Paper and Printing Recipes" by J. Sawtelle Ford
Gallic acid is distinguished from tannic acid by tests (2) and (3).
"Some Constituents of the Poison Ivy Plant: (Rhus Toxicodendron)" by William Anderson Syme
Medicinally, gallic acid has been, and is still, largely used as an astringent, styptic and haemostatic.
"Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 4" by Various
B. Reade produced paper negatives by means of gallic acid and nitrate of silver in 1837.
"The Evolution of Photography" by John Werge
Chemists have extracted from it an astringent liquor containing tannin and gallic acid.
"Curiosities of Medical Experience" by J. G. (John Gideon) Millingen
In my experience ergot in combination with gallic acid and dilute sulphuric acid has been very efficient.
"A System of Practical Medicine by American Authors, Vol. I" by Various
For ink-making the tannin has first to be transformed into gallic acid.
"Encyclopaedia Britannica, 11th Edition, Volume 14, Slice 5" by Various
The former colour is due to gallic acid.
"Animal Proteins" by Hugh Garner Bennett
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