319. Carbon and Water.-Some very important organic compounds have H and O, in the proper proportion to form water, united with C. The three leading ones are sugar, C12H22O11 or C12(H2O)11, starch, C6H10O6, or ?, and cellulose, C18H30O15 or ?. Note the significance of the name carbo-hydrates as applied to them.
320. Sugars may be divided into two