SUGAR, MOLASSES, CONFECTIONS, AND HONEY. 855 



is raised by carnauba wax and certain mineral waxes. Again, the addition of some 

 mineral waxes, of saint wax, and of various mixtures does not change the melting 

 point. 



(2) The addition of mineral waxes, paraffin, tallow, and carnauba wax diminish 

 the free acids, which, on the other hand, increase with the addition of suint wax, 

 suint acids, resin, and stearic acid. With China and Japan wax they do not pass 

 the prescribed limits. 



(3) The entire quantity of acids is diminished by mineral wax, paraffin, and some- 

 what by carnauba wax. They increase slightly with suint wax, and in a greater de- 

 gree with the waxy acids of suint, with resin, tallow, stearic acid, and vegetable 

 waxes. 



VON HUBL'S METHOD FOR EXAMINING WAX*. 



v. Hiibl's method possesses many advantages, but is attended with the disadvantage 

 that many kinds of wax saponify with difficulty. Half an hour's boiling under the 

 inverted condenser seldom suffices, and it is generally necessary to heat the sample 

 in an open flask on the water bath until the alcohol is nearly completely expelled. 

 Waxes containing ceresin almost invariably give saponification numbers much too low. 

 The method gives good results only after long practice. Indeed the commercial 

 chemists using it have often adjudged waxes as adulterated which more carefully 

 examined have been found genuine. For this reason we propose the following altera- 

 tions in it: First, determine the acid number in the usual way with aqueous semi- 

 normal potash. It seems, however, desirable to take 7 to 10 grams, requiring 5 to 7 

 cc seminormal potash ; for with only 3 or 4 grams, the quantity prescribed by v. Hub], 

 errors in titration have too great an influence. 



Instead of determining the " saponification number," we estimate the " total acid 

 number," or, in other words, the amount of potash (calculated as tenths per cents) re- 

 quired by 1 gram of a mixture of fat acids and alcohols obtained by first saponifying 

 a wax with potash and then decomposing the soap with hydrochloric acid. We call 

 this mixture "opened wax" ("aufgeschlossenes Wachs"). The detailed procedure 

 is : Dissolve about 20 grams potash in a hemispherical porcelain dish of 350 to 500 cc. 

 capacity, in 15 cc. of water, heat over a Bunsen burner to incipient boiling, add 20 

 grams of the wax sample, which should have been fused over a water bath, and stir. 

 Continue heating over a low flame, stirring constantly, for ten minutes. Dilute with 

 200 cc. water, heat and acidify with 40 cc. hydrochloric acid, previously diluted 

 slightly. Boil till the floating layer is completely clear ; cool and purify the cake by 

 thrice boiling with water, adding a little hydrochloric acid the first time. Finally 

 lift the cake, wipe with filter paper, dry in the air bath and filter. The filtered wax 

 while still fused is to be poured into a cover glass and after cooling broken in frag- 

 ments. Six to 8 grams of this "opened wax" are heated with neutral alcohol and 

 titrated,' using phenolphtalein as an indicator. The saponificatiou, even with sam- 

 ples containing much ceresiu, is complete. The " total acid number " is somewhat 

 lower than v. Hiibl's "saponification number." Calling the acid number 8, the total 

 acid number S and the ether number a, a -\- a represents the saponification number 

 ofHubl.and: 



56100 (8-8). m 



56100 -18S. 



g_56100(a-f a). , 2 \ 



56100 -f 18 a. 



* R. Benedikt u. K. Mangold, Chem. Zeit., 1891, 28,474. 



