D) a highly spontaneous reaction always occurs rapidly. 9. for an unknown compound the enthalpy of vaporization is found to be 31.7 kj/mol and the entropy of vaporization is found to be 79.9 j/(k mol). calculate the normal boiling point of this compound on the celsius scale. (hint: the reaction is at equilibrium at its boiling point.) a) 124°c b) 3°c c) 48°c d) 0.4°c e) none of these is correct