Q. 41

<span lang="EN-US

Answer :

o The heat of combustion ∆Hc of graphite (i.e. carbon) is given as = 20.7 kJ for 1g of graphite (C).


1 mole of Carbon = 12 g


Hence the molar enthalpy change (enthalpy for 1 mole )


= (20.7 × 12 )= 248.4 KJ mol-1


Since the heat is evolved, the actual molar enthalpy change


= -248.4 KJ mol-1


o In combustion reactions, heat is always evolved i.e. it is an exothermic reaction. Hence the sign of ∆H for the reaction will always be negative (for the process to occur).


Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
caricature
view all courses