I am currently doing the A2 year of the OCR Salter's Chemistry course and am unsure of the correct, markscheme and syllabus approved way to write the electronic configurations concerning the 3d and 4s subshells.
Our AS teacher told us to write 4s before 3d in the configuration, as it is filled before the 3d subshell. This is the way that is written in the AS revision guide.
However this A2 year our teacher has told us to write it in numerical order. As in, even though 4s is filled before 3d we are to write 3d before 4s. And she has said that the markschemes agree with this.
Can anyone shed some light on which way is correct and will gain the marks in an exam
How to write electronic configurations for OCR salters chemistry Watch
- Thread Starter
- 26-12-2010 22:59
- 27-12-2010 12:18
I'm pretty sure, though I don't know exactly for OCR salters because I never did it, that if you put the 4s before the 3d shell then they won't mark it wrong because (well for most compounds - all the ones you'd be dealing with) the 4s is filled before the 3d. Though, saying that, when they are filled the 4s is higher in energy than the 3d so it entirely depends on which way you look at it :P
Sorry I can't be of more help just though it would be useful for you to know the two ways. Can't you look at the markscheme for papers last year, I'm sure the way they're marked will be consistent....
- 27-12-2010 15:28
3d4s is the right way round.