MONOBASIC FATTY ACIDS. 283 



by the action of carbonic oxide on potassium hydrate : 



KHO + CO = KCHO 2 , 



Potassium 

 formate. 



by the action of potassium hydrate on chloroform : 

 CHC1 3 -f 4KHO = 3KC1 + 2H 2 O + KCH0 2 , 



by heating equal parts of glycerine and oxalic acid, when the 

 latter is split up into carbon dioxide and formic acid : 



C 2 H 2 O< = CO 2 + CH,O 2 . 



Oxalic acid. 



It is also a product of the decomposition of sugar, starch, etc. 

 Formic acid is a colorless liquid having a penetrating odor, and 

 a strongly acid taste ; it produces blisters on the skin ; it is a 

 powerful deoxidizer, being then converted into carbon dioxide 

 and water : 



CH 2 O 2 + = C0 2 + H 2 0. 



Acetic acid, H.C 2 H 3 2 , or C 2 H 3 O.HO, or CH 3 .C0 2 H = 60. The 



most important alcohol is ethyl alcohol, and the most important 

 organic acid is acetic acid, obtained from ethyl alcohol by oxida- 

 tion. Acetic acid is found in combination with alkali metals in 

 the juices of many plants, also in the secretions of the glands, etc. 



Acetic acid is chiefly formed either by the oxidation of alcohol 

 (and aldehyde) or by the destructive distillation of wood. It is 

 produced commercially on a large scale as follows : A diluted 

 alcohol (8 to 10 per cent.) is allowed to trickle down slowly 

 through wood-shavings contained in high casks having perfo- 

 rated sides in order to allow a free circulation of the air; the 

 temperature is kept at about 24 to 30, and the liquid having 

 passed through the shavings is repeatedly poured back in order 

 to cause complete oxidation. When the latter object has been 

 accomplished the liquid is a diluted acetic acid. 



The second process for manufacturing acetic acid is the heat- 

 ing of wood to a red heat in iron retorts, when numerous pro- 

 ducts (gases, aqueous and tarry substances) are formed. The 

 aqueous products contain, besides other substances, methyl 

 alcohol and acetic acid. The liquid is neutralized with calcium 



