Compute the heat of formation of liquid methyl alcohol in kilojoules per mole using the following data. The heat of vaporisation of liquid methyl alcohol =38 "kJ/mole". The heats of formation of gaseous atoms from the elements in their standard states: H,218 "kJ/mole", C,715 "kJ/mole", O, 249 "kJ/mole". Average bond energies : C-H=415 "kJ/mole" C-O=356 "kJ/mole" O-H=463 "kJ/mole".

Compute the heat of formation of liquid methyl alcohol in kilojoules p

1.	Compute the heat of formation of liquid methyl alcohol in kilojoules per mole using the following data. The heat of vaporisation of liquid methyl alcohol =38 "kJ/mole". The heats of formation of gaseous atoms from the elements in their standard states: H,218 "kJ/mole", C,715 "kJ/mole", O, 249 "kJ/mole". Average bond energies : C-H=415 "kJ/mole" C-O=356 "kJ/mole" O-H=463 "kJ/mole".
Answer» Solution :`C+2H_(2)+(1)/(2)O_(2) to CH_(3)OH,DELTAH=?` For reactants : HEAT of atomisation of 1 mole of `C=715 kJ` Heat of atomisation of 4moles of `H=4xx218 kJ` Heat of atomisation of 1 mole of `O=249 kJ` For products: Heat of formation of 3 MOLES of C-H bonds `=-3xx415 kJ` Heat of formation of 1 mole of C-O bonds `=-356 kJ` Heat of formation of 1 mole of O-H bonds `=-463 kJ` Heat of CONDENSATION of 1 mole of `CH_(3)OH` to liquid `=-38 kJ` On adding, we get `DeltaH` of formation of `CH_(3)OH` (l). `DeltaH=-266 "kJ mole"^(-1)`.