What is the general formula for alkenes?

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Multiple Choice

What is the general formula for alkenes?

Explanation:
Alkenes are hydrocarbons that contain one or more carbon–carbon double bonds. Because a double bond reduces the number of hydrogens compared with a saturated molecule, the hydrogen count is 2n for n carbons in open-chain alkenes. So the general formula is CnH2n. For example, with 2 carbons you get C2H4 (ethene), with 3 carbons C3H6 (propene), and so on. The alternative formulas point to other types: CnH2n+2 describes alkanes (saturated hydrocarbons), and CnH2n-2 describes alkynes (with a triple bond).

Alkenes are hydrocarbons that contain one or more carbon–carbon double bonds. Because a double bond reduces the number of hydrogens compared with a saturated molecule, the hydrogen count is 2n for n carbons in open-chain alkenes. So the general formula is CnH2n. For example, with 2 carbons you get C2H4 (ethene), with 3 carbons C3H6 (propene), and so on. The alternative formulas point to other types: CnH2n+2 describes alkanes (saturated hydrocarbons), and CnH2n-2 describes alkynes (with a triple bond).

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