Carbohydrates

Carbohydrates are the optically active polyhydroxy aldehyde or ketones or it can be defined as the substance that hydrolize to yield optically active polyhydroxy aldehyde and Ketone are called carbohydrates

Initially it was thought that they are hydrates carbon off formula Cx(H2O)y but rhamanose and deoxyribose did not obey the formula. 

It was also found compounds like acetic acid and formaldehyde which were not carbohydrates but had molecular formula C2(H2O) 2 and C1(H2O)1.

Actually carbon does not form hydrates hence it is when that carbohydrates are hydrates of carbon. 

Classification - 

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