general formula
Alkanes
C(n)H(2n+2)
general formula + functional group
Alkenes
C(n)H(2n)
C=C - a double covalent bond which is an area of high electron density
f.g. isomer: cycloalkanes
Alkenes
C=C bond
C=C has a pi bond which forms when p-orbitals overlap
the presence of this bond means there is restricted rotation around the planar =C< bond
Alkenes
Stereoisomerism in alkenes is
E/Z isomerism
only if each carbon atom of the C=C is bonded to two different groups