The following phrases best describe this reaction : A Endothermic, absorbing energy
Delta H reaction (ΔH) is the amount of heat change between the system and its environment
(ΔH) can be positive (endothermic = requires heat) or negative (exothermic = releasing heat)
∆H positive (endothermic): energy (heat) is absorbed from the environment to the system
∆H negative (exothermic): energy (heat) released from the system to the environment
Reaction
H₂O(g) + energy ⇒ H₂(g) + 1/2O₂(g)
In this reaction, it is shown that to break the bonds on the H₂O molecule to form H₂ and O₂ molecules will require energy (breaking the bonds requires energy)
This energy is usually called ∆H dissociation⁰
