Question

Calculate the standard enthalpy change for the reaction below, given the standard enthalpy of formation values: 2CO(g) + O2(g) → 2CO2(g)ΔH°f (CO) = -110.5 kJ/molΔH°f (O2) = 0 kJ/molΔH°f (CO2) = -393.5 kJ/mol

Answer 1

To calculate the standard enthalpy change  H  for the reaction, we can use the formula:H =  [Hf  products ] -  [Hf  reactants ]For this reaction, the products are 2 moles of CO2 and the reactants are 2 moles of CO and 1 mole of O2.H = [2  Hf  CO2 ] - [2  Hf  CO  + Hf  O2 ]Now, we can plug in the given standard enthalpy of formation values:H = [2   -393.5 kJ/mol ] - [2   -110.5 kJ/mol  + 0 kJ/mol]H = [-787 kJ] - [-221 kJ]H = -566 kJThe standard enthalpy change for the reaction is -566 kJ.