The Student Room Group
Competition - post a photo you've taken of nature >>
Competition - post a photo you've taken of nature >>
Competition - post a photo you've taken of nature >>

chemistry

How would you go about working out this question?

Deduce the element in period 2, from lithium to neon, with the highest second ionisation energy.
Reply 1
Avatar for tuxedo-
tuxedo-
11
The second ionisation energy is the energy required to remove 1 electron from an already ionised once atom (technically its moles but not important for this). The atoms are also in gaseous state for this definition.

I.e. the reaction looks like this X+ -> X2+ + e-

The first ionisation energy is usually highest when you are removing an electron from an atom/element with a full outer shell of electrons already.

So when would you expect the second ionisation energy to be highest?
Reply 2
Avatar for Roha125
Roha125
15
Answer is lithium

If you are well known with 1st ionisation graph of elements(moving from increasing atom number)then just switch every other element with its previous one,Li+ takes position of He(helium has highest 1st ionisation now lithium 1+ has highest)

This switching is done because Li+ now has same number of electrons as Helium atom.
All loses 1 eletron

Untitled.png
Link to webpage for more info-
https://www.differencebetween.com/difference-between-first-and-vs-second-ionization-energy/
(edited 4 years ago)
I think it’s lithium because it’s the smallest atom meaning the negative electron is closest to positive nucleus meaning stronger attraction required to overcome
- also as it’s being removed from the smallest positive Ion it means the attraction is greater
- although there the same shielding, the attraction between nucleus and electron is strongest with the smallest atom that is lithium
Reply 4
Avatar for tuxedo-
tuxedo-
11
Original post by Roha125
Answer is lithium

If you are well known with 1st ionisation graph of elements(moving from increasing atom number)then just switch every other element with its previous one,Li+ takes position of He(helium has highest 1st ionisation now lithium 1+ has highest)

This switching is done because Li+ now has same number of electrons as Helium atom.
All loses 1 eletron

Untitled.png
Link to webpage for more info-
https://www.differencebetween.com/difference-between-first-and-vs-second-ionization-energy/

Giving direct answers isn't helpful, and against the ethos of the website. Especially since OP asked about how to go about solving it, not for the answer.

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you