are organic molecules consisting solely of carbon and hydrogen atoms linked by
single σ bonds.
All the carbon atoms are tetrahedral and sp3
hybridized. Alkanes are stable molecules and unreactive to most chemical
reagents. They have the general formula CnH2n2
are cyclic alkane structures. They have the general formula CnH2n. Most cycloalkanes are unreactive to chemical reagents.
However, three- and four-membered rings are reactive due to ring strain and
behave like alkenes.
Alkanes are organic molecules with the general
formula CnH2n2, which consist of carbon and
hydrogen atoms linked together by C–C and C–H single bonds. They are often
referred to as saturated hydrocarbons
– saturated because all the bonds are single bonds, hydrocarbons because the
only atoms present are carbon and hydrogen. All the carbon atoms in an alkane
are sp3 hybridized and
tetrahedral in shape. The C–C and C–H bonds are strong σ bonds, and so alkanes are unreactive to most chemical reagents.
are sometimes referred
to as straight chain
or acyclic alkanes to distinguish them from cycloalkanes or alicyclic
Cycloalkanes are cyclic alkanes (alicyclic compounds) having the general
formula CnH2n where the carbon atoms have been
linked together to form a ring. All sizes of ring are possible. However, the
most commonly encountered cycloalkane in organic chemistry is the six-membered
ring (cyclohexane). Most cycloalkanes are unreactive to chemical reagents.
However, small three- and four-membered rings are reactive and behave like
alkenes. Such cyclic structures are highly strained since it is impossible for
the carbon atoms to adopt their preferred tetrahedral shape.