[Priore]

I'll like to use Sodium atom as my example here

Na: 1s2 2s2 2p6 3s1
Protons: 11
Electrons 11

From the notes that my teacher gave me, there is an increase in ionisation energy(IE) for successive removal of electrons( 1st IE<2nd IE< 3rd IE...)

Removal of 1st electron forms Na+ ion
Na+: 1s2 2s2 2p6
Protons: 11
Electrons: 10

The removal of another electron from Na+ would result in a large increase in IE as compared to 1st IE, due to the fact that the 2nd electron removed would come from the inner principal quantum shell which is closer to the nucleus thus greater electrostatic attraction between the remaining electrons and the protons. This is as far as i understand.

Here is my question

Shouldnt the IE of the removal of the next 5 electrons starting from Na2+( 1s2 2s2 2p5) be more or less the same, since they are all from the same 2p5 orbitals ( shielding effect and nuclear charge remains constant )? Because i thought there should only be minor fluctuations due to interelectronic repulsion but from the notes my teacher gave, the increase goes in thousands.

Thanks in advance for your replies^^

[macman104]

You are trying to remove an electron from an ever increasingly positive atom.  Each electron means one less negative charge, and thus each one is harder and harder to remove.

[pizza1512]

Technically it should be the same but because you're removing the next 5 electrons from the 2p orbital, the amount of repulsion from the other electrons inside that shell get lower. Allow take not of Hund's rule which states that the electrons will try to spread out as far as possible with in the orbital, and that's where you get the slight '*Ignore me, I am impatient*' between oxygen and nitrogen.

Hope that helps! 

[Vidya]

you have missed one point -nuclear charge is not constant .It is increasing with successive removal of elctrons.
Na+ < Na2+ .

it becomes really difficult to remove an electron from an ion with positive charge.so a manifold increase in IE

[Borek]

you have missed one point -nuclear charge is not constant .It is increasing with successive removal of elctrons.

Nuclear charge IS constant. Charge that you have to deal with when removing next electron is not, but that's not nuclear charge.

[plat_num]

The EFFECTIVE nuclear charge increases.

[Priore]

Technically it should be the same but because you're removing the next 5 electrons from the 2p orbital, the amount of repulsion from the other electrons inside that shell get lower. Allow take not of Hund's rule which states that the electrons will try to spread out as far as possible with in the orbital, and that's where you get the slight '*Ignore me, I am impatient*' between oxygen and nitrogen.

Hope that helps! 

Thanks for your reply. With regards to your statement, i agree that inter electronic repulsion explains the bunp between oxygen and nitrogen. But i'm kinda talking abt successive ionisation energy in an atom. So umm...i didnt quite get an actual ans for that

The EFFECTIVE nuclear charge increases.

Thanks for your replay as well. As far as i know, there are 2 factors affecting effective nuclear charge:
1. Nuclear Charge
2. Shielding effect

Nuclear charge does not increase since 11 protons remains as 11 protons. As for shielding effect, with regards to my example of removing 2p1-2p5 electrons, the 'shields' they have are the same and that would be 1s and 2s orbitals so in my opinion, i think effective nuclear charge did not increase.

[Priore]

Can someone help out a lil bit here?

[Astrokel]

Nuclear charge does not increase since 11 protons remains as 11 protons.

What about the electrons? It's decreasing as successive ionisation energy in an atom. How does this affect the strength of nuclear attraction towards the 'valence' electron in successive ionisation energy in an atom?

It's like

+11  -11 = 0
+11  -10 = +1
+11  -9  = +2
.

Can you see that the nuclear attraction towards the outermost electron is increasing thus what effect has it on the successive ionisation energy?