Thermodynamics — Chemistry STD 11 Science — Question

$(i)\, 6C(s) + 3H_2(g) \to C_6H_6(l) ; \Delta H = +45.9\,kJ$

$(ii)\, H_2(g) +\frac {1}{2}O_2(g) \to H_2O(l) ; \Delta H = -285.9\,kJ$

$(iii) \,C(s) + O_2(g) \to CO_2(g) ; \Delta H = -393.5\,kJ$

.....$kJ$

Reason : $1-$ Butene is more stable than $2-$ butene According to Saytzeff's rule, $2-$ butene should be the product which is more branched or substituted compound and hence, more stable than butene $-1$ 

Between the two tautomers which is more stable ?

Statement $I :$ The presence of weaker $\pi$ - bonds make alkenes less stable than alkanes.

Statement $II :$ The strength of the double bond is greater than that of carbon-carbon single bond.

In the light of the above statements, choose the correct answer from the options given below.