CH. XIIl] QUANTITATIVE. 287 



a — (maltose x '62) = glucose. 

 [The numbers used above are obtained from these data : 

 342 grs. CioHasOii give 360 grs. CgHioOg on inversion. 

 .'. glucose X '95 = cane-sugar or maltose. 

 1 gr. maltose has same reducing power as "62 grs. 



glucose. 

 1 gr. maltose gives 1*05 grs. glucose on inversion. 

 .*. 1 gr. maltose on inversion gives increased reducing 

 power = "43 grs. glucose (I'Oo — "62). 



.• . increase of glucose by inversion of maltose 



X 2*32 = maltose ] 

 An actual example will illustrate use of the above. 

 100 c.c. of an extract : — 



(a) reduced 30 c.c. of Fehling. 



(b) after inversion with citric acid and neutralising, 



38 c.c. Fehling. 



(c) after inversion with hydrochloric acid and neu- 



tralising, 45 c.c. Fehling. 

 (10 c.c. Fehling = '05 grs. glucose.) 

 Then 6 - a = 38 - 30 = 8 c.c. Fehling = '04 grs. glucose. 

 .'. cane-sugar = "04 x "95 = "038 grs. 

 c — 6 = 45 — 38 = 7 c.c. Fehling = '035 grs. glucose. 

 .-. inaltose = '035 x 2*32 = -081 grs. 



a = 30 c.c. Fehling = "loO grs. glucose. 

 .•. original glucose — "150 grs. — ('081 x -id'l) 

 = 1 gr- 



