2 Estimate the stabilization energy for 13pentadiene using t

2. Estimate the stabilization energy for 1,3-pentadiene using the heats of hydrogenation in Table 1 Table 1 Heats of Hydrogenation for Selected Compounds Compound AH(kJ mol) 1-Butene 1-Pentene trans-2-pentene 1,3-Butadiene trans-1,3-Pentadiene -127 -126 -115 -239 -226 2

Solution

The theoretical heat of hydrogenation for 1,3-pentadiene is :

-(126 + 115) kJ/mol = -241 kJ/mol

The experimental/actual value given is -226 kJ/mol.

hence, the stabilization energy is the difference between the two, that is, 15 kJ/mol