Given 2CO(g) + O_2(g) rarr 2CO_2(g)2CO(g)+O2(g)2CO2(g) DeltaH^@=-564*kJ*mol^-1...what is the enthalpy associated with the formation of a mass of 44.0*g of carbon dioxide by these means?

1 Answer
Jan 9, 2017

DeltaH^@=-282*kJ

Explanation:

"2CO +O"_2rarr"2CO"_2 ;DeltaH^@=-564*kJ*mol^-1

DeltaH^@ is always quoted per mole of reaction as written. That is synthesis of 2 moles of carbon dioxide from 2 moles of carbon monoxide and stoichiometric dioxygen has an associated enthalpy change of -564*kJ. Because we combusted 1 mole of carbon monoxide, rather than 2 moles as specified in the equation, the enthalpy calculation is modified and HALVED.........