Weegy: meant by what?
User: what is the difference between hydrocarbons and carbohydrates?
Weegy: Hydrocarbons contain and store a lot of energy in their bonds, and are thus good fuel molecules (gasoline, for example contains a lot of hydrocarbons). [ However, they are strongly hydrophobic (they 'hate' water), so it is very difficult for living cells and organisms to manipulate and use pure hydrocarbons.
About the only use for nearly pure hydrocarbons is wax, which is so strongly hydrophobic that it is used as a waterproofing material.
The carbohydrates are a large, very widely distributed class of compounds found in almost all animals and plants. They are so named because of their basic chemical composition, which is usually some variation on the general formula CH2O. The smallest molecule to be generally considered a carbohydrate is glyceraldehyde, with only three carbon atoms in a short chain. Larger, single, molecules can have up to seven carbon atoms in a chain, but the most common members of this class have 5, or 6 carbon atoms in their structure. The largest molecules are huge polymers of smaller carbohydrate units.
The carbohydrate class can be subdivided into three smaller groups, monosaccharides ('single sugars'), Oligosaccharides (two and three sugars joined together), and Polysaccharides (polymers of many sugars in long chains).
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User: what is the exact definition of alkenes?
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