COMBINATIONS OF OXALIC ACID. g^ 



Hence it follows, that 100 parts of potash are combined 



with 38! of oxalic acid in this salt. And from the preceding 



analyses, compared with this, that 100 parts of potash are 



combined with 



97'§ofacid, in the neutral oxalate. Proportions of 



acid in the 

 three salts. 



]92 in the superoxalate, and acid »n the 



3S1 — — in the quadioxalate. 



These quantities are to each other nearly in the ratio of 

 the numbers I, 2, 4. 



For the knowledge of this curious fact we are indebted to 

 Dr. Wollaston*. I have repeated his experiments, and 

 confirmed their results. 



I endeavoured by other means, to combine potash with a Potash will not 

 larger quantity of acid, but found I could not. Having eva- ^^"^'^^y^*^ 

 porated a solution of quadroxalate of potash, to which I had 

 added a very lar^e quantity of oxalic acid," the first crystal- 

 lization separated the quadroxalate ; and 1 could obtain 

 nothing afterward but crystals of oxalic acid free from 

 potashf. 



Oxalate of soda. 



This is very sparingly soluble in water; in which respect Oxalate of 

 it differs much from the oxalate of potash, which on the'' 

 contrary dissolves very easily in this fluid, 



10 gr. of crystallized oxalic acid were dissolved in water, 

 and neutralized by soda. The oxalate was evaporated to 

 dryness, and heated strongly in a platina crucible. The 

 result was 8'1 gr. of subcarbopate, containing 5*0()4of soda. 

 Hence 100 parts of oxalate of soda consist of 



58-92 oxalic acid, '" componeat 



41-08 soda. P"^'* 



100. 

 And 100 of soda combine with 143*5 of oxalic acid, 



* Bibliolheque Biiianniqae. [Philos. Trans, for 1S07, p. 95: or 

 Journal, vcl, XXl, p. 164] 



f When I bi'gan my experiments, I had procured some svdt of sorrel Salt of sorre: 

 from a very respectable druggist ; and 1 attempted to combin-? it with a sometimes a 

 larger quantity of acid by the methods indicafed by Or. Wol'aston^ but quadroxalate. 

 ■without success. Hence 1 was abou't to conclude, that the quadroxalate 

 did not ex'iit ; when I discovered, that the salt on which 1 was operating 

 was a real quadroxalate. This proves, that the salt of-orre! of theshopsis 

 iomctimes a quadroxalate, and coHseq.uently combined wuii too in uch acid. 



Superoxalafe 



