About 20 gallons of lemon juice should yield about 1 0 lb of crystallized citric acid.
Citric acid, being tribasic, forms either acid monometallic, acid dimetallic or neutral trimetallic salts; thus, mono-, diand tri-potassium and sodium citrates are known.
They are precipitated from their alkaline solutions as cobalt sulphide by sulphuretted hydrogen, but this precipitation is prevented by the presence of citric and tartaric acids; similarly the presence of ammonium salts hinders their precipitation by caustic alkalis.
Moulds have been isolated which occasion the formation of citric acid from glucose.
Considerable trade is done in agro di limone or lemon extract, which forms the basis of citric acid.
The synthesis of citric acid was accomplished by L.
Citric acid has an agreeable sour taste.
Citric acid digested at a temperature below 40° C. with concentrated sulphuric acid gives off carbon monoxide and forms acetone dicarboxylic acid.
On warming citric acid with an excess of lime-water a precipitate of calcium citrate is obtained which is redissolved as the liquid cools.
The impurities occasionally present in commercial citric acid are salts of potassium and sodium, traces of iron, lead and copper derived from the vessels used for its evaporation and crystallization, and free sulphuric, tartaric and even oxalic acid.
Tartaric acid, which is sometimes present in large quantities as an adulterant in commercial citric acid, may be detected in the presence of the latter, by the production of a precipitate of acid potassium tartrate when potassium acetate is added to a cold solution.
Citric acid is also distinguished from tartaric acid by the fact that an ammonia solution of silver tartrate produces a brilliant silver mirror when boiled, whereas silver citrate is reduced only after prolonged ebullition.
Citric acid is used in calico printing, also in the preparation of effervescing draughts, as a refrigerant and sialogogue, and occasionally as an antiscorbutic, instead of fresh lemon juice.
The method introduced by Dyer of dissolving out the mineral constituents of the soil with a i% solution of citric acid, which represents about the average acidity of the roots of most common plants, yields better results.
In soils where the potash available to citric acid is less than.
Graham's work was developed by Liebig, who called into service many organic acids - citric, tartaric, cyanuric, comenic and meconic - and showed that these resembled phosphoric acid; and he established as the criterion of polybasicity the existence of compound salts with different metallic oxides.
(5) Sodii citro-tartras effervescens, a mixture of sugar, sodium bicarbonate, citric and tartaric acids.
In the last years of his life he returned to the vegetable acids, and investigated citric, malic, oxalic and gallic acids.
Such bases occur almost exclusively in the dicotyledons, generally in combination with malic, citric, tartaric or similar plant-acids.
- This includes sulphuric, hydrochloric, nitric, phosphoric, tartaric, citric, acetic and lactic acids, all of which owe their action to their acidity.
The preparations of lithium used in medicine are: Lithii Carbonis, dose 2 to 5 grs.; Lithii Citras, dose 5 to io grs.; and Lithii Citras effervescens, a mixture of citric acid, lithium citrate, tartaric acid and sodium bicarbonate, dose 60 to 120 grs.
When prescribed it is generally rendered more soluble in water by the addition of dilute sulphuric acid or of citric acid, one drop of the former or 4ths of a grain of the latter being used for each grain of the quinine sulphate.
This latter reaction is hindered by the presence of many organic acids (tartaric acid, citric acid, &c.).
Such, for instance, is the preparation of the elements of citric acid, which is manufactured at an establishment at Messina.