Examlex
The first atoms of the Universe (hydrogen and helium)formed within minutes of the Big Bang.How did the other elements form?
Ethene
A colorless flammable gas with a faint sweet and musky odor, the simplest alkene with the chemical formula C2H4, used as a petrochemical precursor.
Constitutional Isomers
Compounds that have the same molecular formula but differ in the connectivity of their atoms, resulting in different chemical structures.
Geometric Isomers
Molecules with the same structural formula but differing in the spatial arrangements of atoms or groups of atoms, due to restricted rotation around a bond.
Alkenes
Hydrocarbons containing at least one carbon-carbon double bond, part of the unsaturated hydrocarbons.
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