AHHHH ... thanks a lot ... makes so much more sense now ... PANIC over
Haha no problem I quite like electronic config, out of all the past papers Chlorine always gets asked and Iodines outer sub-shell has only been asked once!
can anyone explain how a double bond can be nucleophilic if it has got plenty of electrons ( shouldn't it just be electrophilic? ) i'm getting this from the revision guide page 95 by the way.
Haha no problem I quite like electronic config, out of all the past papers Chlorine always gets asked and Iodines outer sub-shell has only been asked once!
yeah it was the iodine one which i was stuck on ... i didn't knw how to work it out cause the mark scheme said 5p6 and i ended up with 4f8 because i went up the spdf scale thing, only knw we could jump from 3p-4s-3d and no more jumping further on, obviously i was wrong -_- ... but this had made things very clear now
can anyone explain how a double bond can be nucleophilic if it has got plenty of electrons ( shouldn't it just be electrophilic? ) i'm getting this from the revision guide page 95 by the way.
Neucleophiles are electron pair donors - so they have many electrons i.e. a lone pair or in this case an electron dense area like a double bond. Electrophiles do not have enough electrons they are electron pair acceptors.
can anyone explain how a double bond can be nucleophilic if it has got plenty of electrons ( shouldn't it just be electrophilic? ) i'm getting this from the revision guide page 95 by the way.
It bonds by donating a pair of lone electrons in a dative covalent bond so a double bond is kind of like a nucleophile.
Although you will be more asked about an electrophile bonding with the double bond not the other way round.
yeah it was the iodine one which i was stuck on ... i didn't knw how to work it out cause the mark scheme said 5p6 and i ended up with 4f8 because i went up the spdf scale thing, only knw we could jump from 3p-4s-3d and no more jumping further on, obviously i was wrong -_- ... but this had made things very clear now
Awesome Yeah we never need to say elements with f anyways so you should be fine
can someone explain half-equations to me please? which end of the equation do you add the electrons?
it depends on the equation e.g if you asked to write a half equation of the formation of chlorine molecules from chloride ions you'd get 2Cl- >Cl2 + 2e but if it was the formation of chloride ions then the half equation would be the other way around, just make sure you read the question carefully
Another question, when doing past papers do you analyses the advance notice it comes with?
i asked my teacher this. He said because it's specific, it's better to see what kind of questions they usually ask with the pre-release. So that's what I do.