hi, I have a question regarding the first ionisation energy and 2nd energy ionisation definition, so basically in a small mini test i wrote the 1st ionisation energy definition as ' the first ionisation energy is the enthalpy change when mole of gaseous 1+ ions is formed from gaseous atoms. ( got the mark for this definition). now here is where the problem comes in, for the second ionisation energy I wrote ' the second ionisation energy is the enthalpy change when one mole of gaseous 2+ ions is formed from one mole of gaseous 1+ ions. I did not get the mark for this question?? and the same exact word to word definition is stated on the cgp revision guide?? then I ask my teacher and she says that the revision guide is wrong despite the 1st ionisation energy definition being right and the second being wrong? does anyone know what's going on?