Ocr f321 23 may 2013~official discussion thread

Well I don't think they've asked the defintion of successive ionisation energy, that could throw some people off and that wouldn't really bother me too much as it'll increase because of the nuclear charge increasing, the atomic radius decreasing and similiar effects from electron shielding as they're within the same outer shell.

Would that be okay for an answer? Obviously going into a bit more detail about it .

Correct! My turn

A shared pair of electrons which has been donated by one of the bonding atoms

Well if we're talking about successive inoisation energies within the same atom, you're right it would increase since (this especially applies to electrons in different shells) as you try and ionise the atom of electrons further in, the atomic radius does decrease and there is less electron shielding so a stronger electrostatic attraction between the nucleus and electrons requiring more energy to over come in order to ionise.
Nuclear charge of the atom (if we're taling about the same one) wouldn't change though...

Write an equation to represent the second ionisation energy of oxygen.

Write an equation to represent the second ionisation energy of oxygen.

Thanks!

O+(g) ----> O2+(g) + e-

O^+(g) ----> O^2+(g) + e-

Sorry if its hard to read :-/

To be quite honest I've never even bothered to learn any of the green coloured pages, also on the periodic table part as I highly doubt that it'll ever show up.

its okay correct answer though

Thanks so much, phew !
Do you get that urge though, to revise EVERYTHING even the 'extra info' bits just incase hah ?

Thanks Explain some properties of water and why water has a higher melting point than NH3.

Some ?

Okay, wtaer has a relatively high boiling and melting point because a lot of energy is needed to overcome the hydrogen bonds. Also ice is less dense than water because as an open lattice with hydrogen bonds.

Higher than NH3 ? Is it because Oxygen is more electronegative than nitrogen ?

does anyone have the 2013 paper and mark scheme??

had a look through the specification and was unsure on what this actually meant (the 'relative energies' part) "Describe the relative energies of s-, p- and d- orbitals for the shells 1, 2, 3 and the 4s and 4p orbitals" can anyone explain please?

I can send it to you via email if you want




Think is saying that electrons fill from low energies (1s2) to higher energies (2s2)

cant you just upload it please