[LGrosvenor101]

(Original post by windo)
For the question "why does amine act as a base" i put - Because it can donate a lone pair of electrons to form a covalent bond. is this wrong or right?

A base is a proton donor, so I don't think thats right, sorry

[otrivine]

(Original post by LGrosvenor101)
A base is a proton donor, so I don't think thats right, sorry

no a base is a proton acceptor acid is proton donor

[LGrosvenor101]

(Original post by otrivine)
no a base is a proton acceptor acid is proton donor

Sorry thats what I meant :') a base is a proton acceptor

[windo]

(Original post by LGrosvenor101)
Sorry thats what I meant :') a base is a proton acceptor

so am i right in saying "Because it can donate a lone pair of electrons to form a covalent bond" or did i have to say the N donates a lone pair of electrons.

[LGrosvenor101]

(Original post by windo)
so am i right in saying "Because it can donate a lone pair of electrons to form a covalent bond" or did i have to say the N donates a lone pair of electrons.

I'm not sure, as you are referring to electrons, when its a proton acceptor :/ and it doesn't donate, it accepts :/

[windo]

(Original post by LGrosvenor101)
I'm not sure, as you are referring to electrons, when its a proton acceptor :/ and it doesn't donate, it accepts :/

well on june 2011 mark sceme it says :-

donates a lone pair (on N)
OR
accepts a proton/H+

and on the guidance section, it says : -

IGNORE ‘forms a dative covalent bond’
(no direction of lone pair)
ALLOW ‘forms a dative covalent bond with/to H+
ALLOW mark for N:H+
(can be from correct equation)

so will i get a mark for saying "Because it can donate a lone pair of electrons to form a covalent bond" or did i have to say the N donates a lone pair of electrons.

[LGrosvenor101]

(Original post by windo)
well on june 2011 mark sceme it says :-

donates a lone pair (on N)
OR
accepts a proton/H+

and on the guidance section, it says : -

IGNORE ‘forms a dative covalent bond’
(no direction of lone pair)
ALLOW ‘forms a dative covalent bond with/to H+
ALLOW mark for N:H+
(can be from correct equation)

so will i get a mark for saying "Because it can donate a lone pair of electrons to form a covalent bond" or did i have to say the N donates a lone pair of electrons.

Well with that, it can go either way to be honest... depends how the examiners are feeling, as the question was referring to why NH2 specifically acts as a base? But yeah, I'm not sure, I'm not an examiner! Hopefully they will give you the mark

[Educator]

there was question where they asked us something about why the amino acids have 2 isoelectric points or something.
i put cause there were 2 different amini acids in the protein given and their functional groups determine the pH of the isoelectric point.it was 2 marks and i wrote something along R group lines i think.
what did you guys put.

[otrivine]

(Original post by Educator)
there was question where they asked us something about why the amino acids have 2 isoelectric points or something.
i put cause there were 2 different amini acids in the protein given and their functional groups determine the pH of the isoelectric point.it was 2 marks and i wrote something along R group lines i think.
what did you guys put.

it was 1 mark question , i wrote like the zwitterion can have no overall charge and i defined isoelectric point something along those lines?
for the gas chromatography for the first one i said use databook values and something else and the second part i said some unfamiliar compounds may have same retenstion time?

[Educator]

(Original post by niaghez)
i lost about 10 or 11 being harsh to myself. but i know i definately got 7 wrong

SAME LMAO !
I think i lost 4-5 marks in the last question and definitely the benzaladehyde.thats around 7/8.than i must've lost some marks somewhere else lol

[Educator]

(Original post by otrivine)
it was 1 mark question , i wrote like the zwitterion can have no overall charge and i defined isoelectric point something along those lines?
for the gas chromatography for the first one i said use databook values and something else and the second part i said some unfamiliar compounds may have same retenstion time?

it also said something like if you can't determine what ester it is.than what technique or spectrometer could be used to dtermine the structue and gain more information.
i said use mass spectrometer,it gives dintinctive fragmentation patters which can be compared with the database vlues :|

[niaghez]

(Original post by Educator)
it also said something like if you can't determine what ester it is.than what technique or spectrometer could be used to dtermine the structue and gain more information.
i said use mass spectrometer,it gives dintinctive fragmentation patters which can be compared with the database vlues :|

i said make a gas chromatogram and analyse the peaks :/

[otrivine]

(Original post by Educator)
it also said something like if you can't determine what ester it is.than what technique or spectrometer could be used to dtermine the structue and gain more information.
i said use mass spectrometer,it gives dintinctive fragmentation patters which can be compared with the database vlues :|

yes i said that too

[niaghez]

(Original post by Wotevatreva)
You missed out the halogen carrier, with bromine. C8h8br3?!?

And the benzaldehyde with ammonium hydroxide and the other two reagents. It was basically giving you the answers as well...

That's it I reckon 60 marks.

halogen carrier with bromine?? was that a one marker somewhere??

[Educator]

(Original post by niaghez)
i said make a gas chromatogram and analyse the peaks :/

i am pretty sure we had to talk about some other technique.thats was three marks.they already had talked about the GC technique in the questionand usually they talk about GC-MS together.so that was the first thing sprung into my mind.tbh i need all the questions in front of me to answer them lol

[Educator]

(Original post by otrivine)
yes i said that too

you and me are in the same boat brother.we'll pass together if we do
if we sink we sink together

[asaaal]

does anyone know the right answer for the 2 step synthisis question yet?

or anyone 99% sure they know?

[otrivine]

(Original post by Educator)
you and me are in the same boat brother.we'll pass together if we do
if we sink we sink together

oh no that say that loool we pass what u think u got

[otrivine]

(Original post by asaaal)
does anyone know the right answer for the 2 step synthisis question yet?

or anyone 99% sure they know?

i put aq NABH4 then said conc h2so4 , heat under reflux and for extra info just in case to gurantee me the marks i said K2CR2O7

[SmithytheDrummer]

(Original post by Educator)
it also said something like if you can't determine what ester it is.than what technique or spectrometer could be used to dtermine the structue and gain more information.
i said use mass spectrometer,it gives dintinctive fragmentation patters which can be compared with the database vlues :|

In that question it didn't mention the MS only GC