danam04
contestada

The enthalpy change for the reaction, 2CO (g) + O2 (g) 2 CO2 (g), can be calculated from ΔHf values for each reactant and product. Which substance or substances in this equation have a ΔHf value equal to 0.0 kilojoules?
O2 (g)
CO (g)
O2 (g) and CO (g)
CO2 (g)

Respuesta :

O2 has a value close to 0KJ

Answer:

Oxygen (O₂) will have ΔHf equal to 0.0 kJ.

Explanation:

The enthalpy of formation of elements in their native state is considered to be zero. Oxygen in nature occurs as O₂, so its enthalpy of formation will be zero.

the other given species are not elements, they are compounds.

CO and CO₂ both are compounds so they cannot have enthalpy of formation equal to zero.