H H H Relative Stabilities cumulated terminal diene alkyne 1,2-pentadiene 1-pentyne nternal alkyne twice I-pentene 2-pentyne kcal isolated 69.5 diene more substituted isolated 1. 4-pentadiene 65.8 diene trans-14-hexadiene conjugated 60.2 diene kcal 57.4 kcal trans-1, 3-pentadiene kcal alkane(pentane or hexane > Chaper 15Chaper 15 4 Relative Stabilities twice 1-pentene more substituted =>