First Ionization Energy Trends for Period 2 Elements

Yes it does

and for the same reason!!
EDIT: well....(2s to 2p, but near enough)

:biggrin:

Reply 2

OP

and that's roughly because there's more shielding from the s orbital, right?
I'm re-revising Modules 1-3 for the synoptic A2 paper lol and I'm really rusty

Reply 3

When in comparison with the s orbital the p orbital electron is already at a higher energy....so it takes less to remove it...
thats basically why!!

Reply 4

Guaglio

and that's roughly because there's more shielding from the s orbital, right?
I'm re-revising Modules 1-3 for the synoptic A2 paper lol and I'm really rusty

On crossing over from the 2s to 2p or 3s to 3p, there is a drop in IE. This is due to that fact that the p orbitals are less penetrating than the s orbitals, hence they lie away from the nucleus further more than the s orbitals, hence experience less of the total nuclear charge. So, it is easier to remove the valence electron.

Shielding doesn't actually affect much across a period, it is however very important for IE down a group.

Reply 5

OP

shengoc

On crossing over from the 2s to 2p or 3s to 3p, there is a drop in IE. This is due to that fact that the p orbitals are less penetrating than the s orbitals, hence they lie away from the nucleus further more than the s orbitals, hence experience less of the total nuclear charge. So, it is easier to remove the valence electron.

Shielding doesn't actually affect much across a period, it is however very important for IE down a group.

when you say they're less penetrating, do you mean they're further from the nucleus? if that's what you mean, then surely that distance would have a very minimal effect on IE, and there wouldn't be such a distinct drop in 1st IE from s to p ?

Reply 6

Guaglio

when you say they're less penetrating, do you mean they're further from the nucleus? if that's what you mean, then surely that distance would have a very minimal effect on IE, and there wouldn't be such a distinct drop in 1st IE from s to p ?

Its because they're further out from the nucleus, so the electrons in that orbital (p) have higher energies than in the s orbital, the differences between the two energy levels may be small but are enough to cause a big drop in energy required! Its not really the distance but the energy of the orbitals

Reply 7

OP

kk thanks

Reply 8

Guaglio

when you say they're less penetrating, do you mean they're further from the nucleus? if that's what you mean, then surely that distance would have a very minimal effect on IE, and there wouldn't be such a distinct drop in 1st IE from s to p ?

I am probably speaking in terms of an undergraduate level of chemistry, but then, if you think about it, electrons in a 2p have higher probability density further away from the nucleus compared to the 2s electrons(cf 3p and 3s)

Electrons are bound, so their energies are negative. So electrons further away from the nucleus experience less penetration because of this, but also because the 2p penetrates less than 2s, hence lower effective nuclear charge. Therefore such a drop happens.

This is different when going from N to O, these happens because of what happens in the p orbital alone, no transition involved. I hope I haven't overcomplicated things.

Reply 9

OP

I still don't fully understand your use of the word penetrate. This is for A2, btw

Reply 10

Guaglio

I still don't fully understand your use of the word penetrate. This is for A2, btw

Forget about penetration then. However, there definitely wasn't enough shielding to cause such a drop across a period. It is down to the fact that the energy of the p orbital is slightly higher than the s orbital.

Reply 11

shengoc

Forget about penetration then. However, there definitely wasn't enough shielding to cause such a drop across a period. It is down to the fact that the energy of the p orbital is slightly higher than the s orbital.

(nobody take offence by this please, not meant viciously)
as we've all been saying!

isn't it amazing the ways people use to exaplain the same (essentially) thing!
:rolleyes:

Reply 12

raceforthefishman

(nobody take offence by this please, not meant viciously)
as we've all been saying!

isn't it amazing the ways people use to exaplain the same (essentially) thing!
:rolleyes:

It is just that as you go up to a higher level of learning ladder, things start to get more detailed, but that is also why it gets interesting.

Reply 13

shengoc

It is just that as you go up to a higher level of learning ladder, things start to get more detailed, but that is also why it gets interesting.

Ye, although GCSE was a definate low point due to 21st cnetury crap we had to do :frown:

anyways...are your ionisation queries solved now? :smile:

Reply 14