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First ionisation energy equations.. help?!

1. I've just started year one A levels and I've been set questions on the first chapter of the textbook. There's some easy questions about TOF mass spectrometry and basic atomic configuration, but we've been set the end of chapter questions to do when were only on page 10, we haven't covered half the chapter. The teacher expects us to do ALL the questions, but most of them are about "first ionisation energy"? And the equations and rearranging it.. I've read the textbook, explanations online and nothing is going in, I'm tired anyway and I just don't understand it for some reason? I'm normally good at learning new information but it's really stressing me out and I need to somehow answer really obscure questions on concepts I haven't been taught yet and don't understand. Can anyone try and dumb it down for me a bit? Thanks
CheeseIsVeg & anyone else who can actually do chemistry (not me)
2. Are there any specific questions you have?

1st IE is just the energy required to remove one mole of electrons from one mole of atoms in the gas phase. The more tightly bound the highest energy electron is, the higher the 1st IE.
3. (Original post by alow)
Are there any specific questions you have?

1st IE is just the energy required to remove one mole of electrons from one mole of atoms in the gas phase. The more tightly bound the highest energy electron is, the higher the 1st IE.
I just don't understand how you work out the energies or what the equation is, and how a higher energy level needs more energy since it's further away from the nucleus. I thought a mole was to do with neutrons and protons so confused
4. (Original post by LDS16)
I just don't understand how you work out the energies or what the equation is, and how a higher energy level needs more energy since it's further away from the nucleus. I thought a mole was to do with neutrons and protons so confused
Nope a mole is just an amount. With ionisation energy, the units are kJ per mol because that's how many kilojoules it would take to remove 6.02 x 10^23 of that specific electron in that specific position.

I don't think you ever need to do calculations with ionisation energy, you just have to be able to compare data and explain it.

Also, higher energy level requires LESS energy to remove an electron.
5. (Original post by LDS16)
I've just started year one A levels and I've been set questions on the first chapter of the textbook. There's some easy questions about TOF mass spectrometry and basic atomic configuration, but we've been set the end of chapter questions to do when were only on page 10, we haven't covered half the chapter. The teacher expects us to do ALL the questions, but most of them are about "first ionisation energy"? And the equations and rearranging it.. I've read the textbook, explanations online and nothing is going in, I'm tired anyway and I just don't understand it for some reason? I'm normally good at learning new information but it's really stressing me out and I need to somehow answer really obscure questions on concepts I haven't been taught yet and don't understand. Can anyone try and dumb it down for me a bit? Thanks
CheeseIsVeg & anyone else who can actually do chemistry (not me)
First ionisation energy = the amount of energy required to remove 1 mole of electrons from 1 mole of gaseous atoms to form 1 mole of gaseous ions with a 1+ charge

Equations relating first ionisation energy usually are in the form: X (g) --> X^+(g) + e^-
The electron removed = e^-
Hope this makes sense, feel free to post the question, ask more questions
6. (Original post by richpanda)
Nope a mole is just an amount. With ionisation energy, the units are kJ per mol because that's how many kilojoules it would take to remove 6.02 x 10^23 of that specific electron in that specific position.

I don't think you ever need to do calculations with ionisation energy, you just have to be able to compare data and explain it.

Also, higher energy level requires LESS energy to remove an electron.
Thanks for your help, I appreciate it. But 6.022x10²³ electrons is a huge amount, surely?? How do you find out the energy required to remove the electrons in a particular element, like the 16 in Oxygen? Or is that not possible? Sorry for being so stupid aha
7. (Original post by CheeseIsVeg)
First ionisation energy = the amount of energy required to remove 1 mole of electrons from 1 mole of gaseous atoms to form 1 mole of gaseous ions with a 1+ charge

Equations relating first ionisation energy usually are in the form: X (g) --> X^+(g) + e^-
The electron removed = e^-
Hope this makes sense, feel free to post the question, ask more questions
Thanks for the reply Cheese, but no not really
What is the electron which is removed to the power of? (The "^" )
I don't really want to just get the answers as I really want to understand it myself, not going well atm aha
8. (Original post by LDS16)
Thanks for the reply Cheese, but no not really
What is the electron which is removed to the power of? (The "^" )
I don't really want to just get the answers as I really want to understand it myself, not going well atm aha
Basically an electron has a relative charge of -1, therefore it is put to the power of -1 (^-)

I'm not going to confuse you by telling you the actual charge in Coulombs, even though I really want to

Anything else?
9. (Original post by LDS16)
I just don't understand how you work out the energies or what the equation is, and how a higher energy level needs more energy since it's further away from the nucleus. I thought a mole was to do with neutrons and protons so confused
An electron in a higher energy level needs less energy to be removed.

10. (Original post by CheeseIsVeg)
I'm not going to confuse you by telling you the actual charge in Coulombs, even though I really want to
is the actual charge, the Coulomb is just an arbitrarily defined unit.
11. (Original post by alow)
is the actual charge, the Coulomb is just an arbitrarily defined unit.
12. (Original post by CheeseIsVeg)
Basically an electron has a relative charge of -1, therefore it is put to the power of -1 (^-)

I'm not going to confuse you by telling you the actual charge in Coulombs, even though I really want to

Anything else?
I don't even want to know what that is lol
13. (Original post by alow)
An electron in a higher energy level needs less energy to be removed.

Thanks for that, very useful website
14. (Original post by LDS16)
I don't even want to know what that is lol
Feed me Chemistry questions
15. (Original post by CheeseIsVeg)
Feed me Chemistry questions
Okay, here's one-
"State which of the first, second or third ionisations of aluminium would produce an ion with the electron configuration 1s² 2s² 2p^6 3s¹"

Correct me if I'm wrong but I think the energy levels go like this: 1s; 2s 2p2p2p; 3s 3p3p3p 3d3d3d3d3d and so on, so id somehow use this info to get an answer lol
16. (Original post by LDS16)
Okay, here's one-
"State which of the first, second or third ionisations of aluminium would produce an ion with the electron configuration 1s² 2s² 2p^6 3s¹"

Correct me if I'm wrong but I think the energy levels go like this: 1s; 2s 2p2p2p; 3s 3p3p3p 3d3d3d3d3d and so on, so id somehow use this info to get an answer lol
How many electrons has a neutral aluminium atom got?
What does it have to do to get the number of electrons of the ion in the question?
17. (Original post by charco)
How many electrons has a neutral aluminium atom got?
What does it have to do to get the number of electrons of the ion in the question?
13 electrons, and I'm not sure but I guess lose them through ionisation, perhaps by a negative electric current?
18. (Original post by LDS16)
13 electrons, and I'm not sure but I guess lose them through ionisation, perhaps by a negative electric current?
I meant "how many electrons must it lose to attain the configuration in the question?"
19. (Original post by LDS16)
Okay, here's one-
"State which of the first, second or third ionisations of aluminium would produce an ion with the electron configuration 1s² 2s² 2p^6 3s¹"

Correct me if I'm wrong but I think the energy levels go like this: 1s; 2s 2p2p2p; 3s 3p3p3p 3d3d3d3d3d and so on, so id somehow use this info to get an answer lol
Actually energy levels go 1s^2 2s^2 2p^6 3s^2 3p^1 (for aluminium which had 13 electrons)

So for each respective ionisation just take off an electron if there are no electrons left in that she'll then you don't write it in the configuration

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20. (Original post by LDS16)
Okay, here's one-
"State which of the first, second or third ionisations of aluminium would produce an ion with the electron configuration 1s² 2s² 2p^6 3s¹"

Correct me if I'm wrong but I think the energy levels go like this: 1s; 2s 2p2p2p; 3s 3p3p3p 3d3d3d3d3d and so on, so id somehow use this info to get an answer lol
You are along the right lines.
So Aluminium has 13 electrons
These lie in the 1s2 2s2 2p6 3s2 3p1 sub shells
the question ends in 3s1
I have bolded where 3s1 is in aluminium's full electronic configuration
How many ionisations is this?Well 3p1 = 1, to get to 3s1 we then knock off another electron, therefore it would be 2nd ionisation (2 electrons lost )

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