184) The bond enthalpies of H₂, X₂ and HX are in the ratio of 2:1:2. Enthaply of formation of HX is −50KJ⁄mol. The bond enthalpy of X₂ is:

185) The difference between the heat change at constant pressure and that at constant volume for the combustion of 46 gm of ethanol at 27^oC is:

186) For a reaction at 25^oC, enthalpy change ΔH and entropy change ΔS are −11 x 10³ and 10⁵ J⁄mol K respectively, then which of the following statements is true?

187) Enthaply of carbon, hydrogen and ethyl alcohol on combsution at 25^oC are −94, −68.4 and −327 kcal⁄mol, then the formation enthalpy of ethyl alcohol will be:

188) The work of expansion for a system is 500 cal. The heat given to the system is 80 cal. The change in internal energy in the process will be: