Carbohydrates are polyhydroxy aldehydes and ketones and those compounds Which on hydrolysis give such compounds are also carbohydrates. The Carbohydrates which are not hydrolysed are called monosaccharide’s. Other Carbohydrates are oligosaccharides and polysaccharides. Monosaccharides With aldehydic group are called aldose and with free ketonic group are called Ketose. Carbohydrates are optically active. Number of optical isomers = 2ⁿ
Where, n=number of asymmetric carbons.