Carbohydrates indicate to a group of organic compounds which includes C, O, and H
generally in the form of 1: 2: 1 ratio and mainly comprises of cellulose, sugars, starch etc.
Formerly, the carbohydrates are observed as hydrates of carbon and resemble to general formula
(C.H2O) n. But the name of the group 'carbohydrates' occasionally found misleading because: (i)
some organic compounds e.g., acetic acid (CH3COOH), formaldehyde (HCHO), inositol
(C6H12O6), lactic acid (C3H6O1), etc. corresponds to the general formula but is not carbohydrates.
(ii) It is found that the above general formula does not correspond to some carbohydrates e.g.,
digitoxose (C6H12O4), rhamnose (C6H12O5), rhamnohexose (C7H14O6) (iii) besides comprising of
C, O and H, some carbohydrates also carry sulphur and nitrogen. Thus, the carbohydrates are
more suitably referred to as polyhydroxyaldehydes and their derivatives or the substances which
yield these on hydrolysis.
