Q.Name the following: Arrange the three isomers of alkane with molecular formula C5H12 in increasing order of boiling points and write their IUPAC names.

Because carbon and hydrogen have almost identical electronegativity, alkanes are essentially non-polar molecules held together only by weak van der Waals (London dispersion) forces, whose strength scales directly with how much surface area two neighbouring molecules can bring into contact. A straight-chain alkane, able to lie alongside its neighbours over its full length, therefore has stronger intermolecular attraction -- and correspondingly higher melting and boiling points -- than a more compact, branched isomer of the same molecular formula. This same non-polarity explains why alkanes are insoluble in water (a polar solvent) but freely soluble in non …