Chemistry - GOC Question with Solution | TestHub

Pentane and isopentane have 5 carbons and isobutane has 4, so isobutane has the smallest value. Between the $C_5$ isomers, the branched isomer is more stable, so pentane gives out more heat than isopentane. Order : b $>$ c $>$ a (pentane $>$ isopentane $>$ isobutane).