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What is the general formula for alkanes and how does it differ from alkenes?

The general formula for alkanes is CnH2n+2, while alkenes have the formula CnH2n.

Alkanes are hydrocarbons that contain only single bonds between carbon atoms. The general formula for alkanes is CnH2n+2, where n is the number of carbon atoms in the molecule. For example, methane (CH4) is the simplest alkane and has one carbon atom, so its formula is C1H4. Ethane (C2H6) has two carbon atoms, so its formula is C2H6. Alkanes are saturated hydrocarbons, meaning that they have the maximum number of hydrogen atoms possible for their carbon chain.

Alkenes, on the other hand, are hydrocarbons that contain at least one double bond between carbon atoms. The general formula for alkenes is CnH2n, where n is the number of carbon atoms in the molecule. For example, ethene (C2H4) is the simplest alkene and has two carbon atoms, so its formula is C2H4. Alkenes are unsaturated hydrocarbons, meaning that they have fewer hydrogen atoms than the corresponding alkane with the same number of carbon atoms.

In summary, the general formula for alkanes is CnH2n+2, while the general formula for alkenes is CnH2n. Alkanes have only single bonds between carbon atoms and are saturated hydrocarbons, while alkenes have at least one double bond between carbon atoms and are unsaturated hydrocarbons.

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