Question

3. (6 marks) An important industrial method for producing extremely pure ethanoic acid is the reaction of methanol with carbon monoxide. NOTE: Not all lone pairs are included in the structures below. o=0 H2C-OH + CO - > H2C-6-OH Calculate AH of this overall reaction in kJ/mol. The following table of bond energies may contain values to assist you. YOU MUST SHOW YOUR WORK TO GET CREDIT FOR THIS QUESTION. C-H 414 kJ/mol C-O 360 kJ/mol C-C 347 kJ/mol 0-0 142 kJ/mol O-H 464 kJ/mol C=O 736 kJ/mol CEC 611 kJ/mol O=O 498 kJ/mol H-H 436 kJ/mol C=0 1072 kJ/mol C=C 837 kJ/mol

Answer 1

Delta H reaction = [Bond energies of bonds broken in reactants - bond energiesbonds formed in products]

= [ (1x C-O) + (1xC=O) ] - [ (1xC-C) + (1xC=O) + (1xC-O)] { no C-H or O-H bond broken or formed}

= [ 360 +1072] - [ 347 +736+360] kJ

= -11 kJ/mol