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Carbohydrates 糖类 江苏省常州高级中学 房寿高 Question: Are all the carbohydrates sweet? The sweet substance belongs to carbohydrate ? Starch(淀粉）、cellulose [‘seljul?us] （纤维素）etc. are not sweet,but they belong to carbohydrates. and the sweet substances are not always the carbohydrates,such as saccharin（糖精） 1. What is the carbohydrate? A carbohydrate is an organic compound that consists only of carbon, hydrogen, and oxygen, usually with a hydrogen:oxygen atom ratio of 2:1 (as in water). in other words, with the empirical formula Cm(H2O)n. Just for this reason ,it is called carbohydrate (碳水化合物）. Some exceptions exist,for example, deoxyribose [di:,?ksi‘raib?us]（脱氧核糖） , a component of DNA, has the empirical formula C5H10O4.) At the same time , a component of acetic acid has the formula C2H4O2 [C2(H2O)2],but i