Units for Enthalpy

[BB Dis 1H]

Why is delta H sometimes given as J or kJ, but then other times it is given as J/mol or kJ/mol? Are both correct? If so, how do we know when to use each one?
Thanks in advance!

[CindyMorales1H]

Both are correct and you may use both, just make sure to convert to match any other variables (for example the gas constant R is usually in joules, so you would just convert to kj to get an accurate equation)

[Nicole Coulter]

Yes both are correct, one is just denoting the change in enthalpy for the reaction (and whatever the stoichiometric coefficients are is the amount of mols it is referring to, however with the per-mole that would indicate a coefficient of 1, so if you wanted to find enthalpy change with a certain amount of moles or grams it would be need to be done with per-mole or first the enthalpy converted to per-mole for that type of question

[405981594]

When ΔH is given in J or kJ, it represents the total energy change associated with the reaction regardless of the amount of substance involved.
When ΔH is given in J/M or kJ/M, it represents the amount of energy absorbed or released per mole of reactant consumed or product formed during the reaction.

[406011420 Dis 1C]

ΔH can be expressed in J or kJ when representing the total heat energy change for a reaction or process. It can be given in J/mol or kJ/mol to denote the heat energy change per mole of substance involved. The choice depends on whether the focus is on the total energy change or the energy change per mole, but both are correct.

[605988349]

Both are correct, but depending on the question being asked, make sure to match up the units all together. So if you're looking to convert J to kJ, you would have to divide by 1000 and if you're looking to convert kJ to J, you would have to multiply by 1000.

Hope this helps !!