Jones — Action of Cm^hon Dioxide on the Borates^ etc. 49 



Aet. XL — The Action of Carbon Dioxide on the Borates 

 of Barium ; bj Louis Cleveland Jones. 



[Contributions from the Kent Chemical Laboratory of Yale University— CVITI.] 



In 1888 Morse and Burton described "A Method for the 

 Separation and Determination of Boric Acid."* I published 

 an article in 1898 entitled "The Action of Carbon Dioxide 

 on Soluble Borates,"f an account of certain results not in accord 

 with those of Morse and Burton. More recently:}: Morse and 

 Horn record at some length " preliminary experiments " made 

 in an effort to substantiate the original analytical results of 

 Morse and Burton. 



I have waited for some time for the promised resumption of 

 these experiments, and lest further silence be misunderstood, 

 will show that the action of carbon dioxide and boric acid, in 

 the presence of the one base — barium hydrate — both in the 

 dry state and in solution, is that which I pointed out in my 

 original paper, and, further, that these later experiments of 

 Morse and Horn, correctly interpreted, completely substan- 

 tiate this position. 



The question is concerning the action of carbon dioxide gas 

 "upon a mixture containing boric acid and an excess of barium 

 hydrate, viz: what part of the total barium is converted into 

 carbonate and, upon evaporation and ignition, how much, if 

 any, of this barium carbonate is reconverted into borate ? 

 Indirectly, and stated differently, it is : Can boric acid, when 

 once separated, be brought into definite and weighable condi- 

 tion by the method recommended by Morse and Burton ? 

 (Loc. cit.) Despite the title of the contribution of Morse and 

 Burton, Morse and Horn now regard the separation of the 

 boric acid "as the most, and in fact the only, important feature 

 of their contribution." 



The following is the entire description of that part of the 

 process relating to the determination of the boric acid as 

 originally given by Morse and Burton : " The quantity of the 

 dilute barium hydroxide solution" (about 25^^^) " which is 

 equivalent to 25°° of the standard sulphuric acid " (iVyiO) " is 

 run into the flask, and the apparatus attached to a filter-pump." 

 This is done preparatory to receiving the alcoholic solution of 

 boric acid — a little over 75°°. ''Finally^ the excess of the 

 hariurn hydroxide is precipitated hy passing into it a current 

 of carhon dioxide : the contents of the flash are transferred to 



*Am. Chem. Jour., March, 1888, voL x, pp. 154-158. 

 t This Journal, voL v, pp. 442-446, June, 1898. 

 X Am. Chem. Jour., August, 1900, vol. xxiv. 



Am. Jour. Scl— Fourth Series, Vol, XIY, No. 79. — July, 1902. 



