The compound shown is but-1-ene. Count all isomers of its molecular formula C4H8: all constitutional isomers (open-chain and cyclic) together with all geometrical isomers. Give the answer as an integer.

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The compound shown is but-1-ene. Count all isomers of its molecular formula $C X_{4} H X_{8}$ : all constitutional isomers (open-chain and cyclic) together with all geometrical isomers. Give the answer as an integer.

Numerical answer type, tolerance 0.5.

Answer: 6

C X_{4} H X_{8}

has one degree of unsaturation, so the isomers are alkenes or cycloalkanes. Alkenes: but-1-ene, but-2-ene and 2-methylpropene (3 constitutional isomers). But-2-ene exists as cis and trans forms, adding one more. Cycloalkanes: cyclobutane and methylcyclopropane (2). None of these has a stereocentre. Total = 3 + 1 + 2 = 6.

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The compound shown is but-1-ene. Count all isomers of its molecular formula CX4​HX8​: all constitutional isomers (open-chain and cyclic) together with all geometrical isomers. Give the answer as an integer.

Answer: 6

More questions on Isomer counting for a given molecular formula including stereoisomers

The compound shown is but-1-ene. Count all isomers of its molecular formula $C X_{4} H X_{8}$ : all constitutional isomers (open-chain and cyclic) together with all geometrical isomers. Give the answer as an integer.