Chemistry: Post your doubts here!

[Namehere]

Heyy guyss.... i am a little confused here....

so let's say that u have two hypotheticaal equations...

they have the reduction potentials of -0.15 and -1.15
which one of them will be reduced and which will be oxidised??

The more negative one will undergo oxidation, the more positive one will undergo reduction.

So, the -0.15 will get reduced, while the -1.15 will get oxidised.

 

[AbbbbY]

Don´t you use filter paper soaked with a bit of acidified potassium dichromate and when SO2 reaches it, it goes from orange to green? Not sure, maybe I´m wrong.

That's no longer part of the A Level practical syllabus AFAIK. They've also removed Pb ions.

 

[Suchal Riaz]

Please help me asap

 

[..sacrifice4Revenge..]

The more negative one will undergo oxidation, the more positive one will undergo reduction.

So, the -0.15 will get reduced, while the -1.15 will get oxidised.

this is A2 right? cz I dont get a word of it. :S

Please help me asap
View attachment 41543

which paper?
i'll try.

 

[Suchal Riaz]

no it's As. i have figured it out. thanks for pretending to help.

this is A2 right? cz I dont get a word of it. :S



which paper?
i'll try.

ene

 

[Namehere]

this is A2 right? cz I dont get a word of it. :S



which paper?
i'll try.

Well, you were talking about reduction potentials.. which I think is A2. Don´t listen too much to me though, I´m a very "mistaky" person...

 

[..sacrifice4Revenge..]

no it's As. i have figured it out. thanks for pretending to help.

ene

K.

 

[Suchal Riaz]

Well, you were talking about reduction potentials.. which I think is A2. Don´t listen too much to me though, I´m a very "mistaky" person...

i was talking about my question not that one.

 

[hope4thebest]

Does anyone here have any diagram of electrophoresis? I mean an easy one because Marking schemes shows 3D diagrams. Thank You Suchal Riaz AbbbbY Namehere

 

[omaaaar]

The P2 chemistry paper was such a big piece of cake never seen such an easy paper
The easiest organic chemistry question of the century I must say

 

[Syeda Rida Rizvi]

The P2 chemistry paper was such a big piece of cake never seen such an easy paper
The easiest organic chemistry question of the century I must say

I agree!

 

[kitkat <3 :P]

Please help me asap
View attachment 41543

I think Pb2+ should be In FB8 as the first test will have the same result for Al3+ ans Pb2+ and the yellow ppt is given with sol with Pb2+ in it
FB7 has Zn2+ ions cuz its producing soluble ppt with OH- ions ehich are present in FB5
About the sulfate ions m not sure :/ but Pb2+ gives white ppt with SO4 ^2- so maybe its FB7 :/ hope m not too late

 

[Browny]

Can anybody tell me the errors for the apparatus we normally get for the practical exam?

 

[Logitech]

any idea about p31 guys?

 

[zain ul abidin]

Is this V1? bcz i got X=1 For Variant One !

it's varient 2

 

[zain ul abidin]

How did you calculate the molar mass of the compound?

But wasnt the no of moles of the compound = 6.3/0.01, since there were 0.05/5=0.01 moles of it

Mr was 126

 

[Snowysangel]

Mr was 126

How? We did have to divide .05 by 5 right cause the number if moles of the hydrated compound was 1 while in the equation it was 5..

 

[Snowysangel]

How? We did have to divide .05 by 5 right cause the number if moles of the hydrated compound was 1 while in the equation it was 5..

And if you divide 126-90 by 18, you do get 2...but if you divide 630-90 by 18 you get 30

 

[Snowysangel]

And if you divide 126-90 by 18, you do get 2...but if you divide 630-90 by 18 you get 30

And 126=6.3/0.05

 

[AbbbbY]

The P2 chemistry paper was such a big piece of cake never seen such an easy paper
The easiest organic chemistry question of the century I must say

Agreed.

Although, the paper had a few places where people could drop marks.
A lot of people seem to have dropped marks in making the ketone.

Another common mistake was in the isomers question. The question asked for 3 different structural formulae of C6H12 that showed cis-trans but a lot of ppl made the cis & the trans isomers of the same structure. Regardless, should be an easy A for most despite the slightly increased GT that I'm expecting for this paper.