Question

35. Using bond energy data, calculate heat of formation
of isoprene
5C(s) + 4H,(g) → H,C=C-CH=CH,
CH,
Given : BE for C-H, H-H, C-C, C = C and C(s) -
C(g) respectively as 98.8 kcal, 104 kcal, 83 kcal,
147 kcal, 171 kcal
(1) – 20.6 kcal
(2) 20.6 kcal
(3) 40 kcal
(4) 50 kcal
​

Answer 1

35. Using bond energy data, calculate heat of formation

of isoprene

5C(s) + 4H,(g) → H,C=C-CH=CH,

CH,

Given : BE for C-H, H-H, C-C, C = C and C(s) -

C(g) respectively as 98.8 kcal, 104 kcal, 83 kcal,

147 kcal, 171 kcal

(1) – 20.6 kcal

(2) 20.6 kcal✔️✔️✔️

(3) 40 kcal

(4) 50 kcal