Chemistry: Post your doubts here!

[princessnoor]

plz

Huger game
Best of luck thanks for your time

can u answer my question above

 

[Suchal Riaz]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w11_qp_12.pdf
Q37 (D) why the first statement is correct? I mean the empirical formula has 1 atom of O, so there must be aldehyde :/

sorry wrong answer.
correct answer is that as the molecular formula shows that there are 4 carbon and 10 hydrogen, it must be an alcohol as any C=O will decrease the number of hydrogen by 2. it has general formula CnH2n-2O. ketones/aldehydes have formula CnH2nO

 

[Kamihus]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w11_qp_12.pdf
Q37 (D) why the first statement is correct? I mean the empirical formula has 1 atom of O, so there must be aldehyde :/

it can be aldehyde or ketone. both contain only one C=O

Wrong. Cannot be aldehyde as molecular formula contains 10 H but butanal would contain 8 H.

 

[MiniSacBall]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s11_qp_11.pdf

Q13, i don't how to get this, i have got volume as 60 cm3, how is it 30 cm3

 

[ZaqZainab]

plz

can u answer my question above

Can you tell the paper?

 

[Suchal Riaz]

guys plzz answer my question
in an experiment b mol of HI were put into a sealed vessel under pressure p.
ateqilibrium ,x mol of HI had dissociated
2HI--- H2 +I2
now tell how its answer is
i dont get how the 4 came

i don't understand your question. what is for and what is x2/4(b-x)2

 

[SIstudy]

it can be aldehyde or ketone. both contain only one C=O

it could be an aldehyde rite?
but according to the answer its sayin tht this result cant be obtained :'( :'(

 

[ZaqZainab]

sorry wrong answer.
correct answer is that as the molecular formula shows that there are 4 carbon and 10 hydrogen, it must be an alcohol as any C=O will decrease the number of hydrogen by 2. it has general formula CnH2n-2O. ketones/aldehydes have formula CnH2nO

You really need some sleep or maybe just coffee will do

 

[$$AK$$]

Hey
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w12_qp_11.pdf
Q1-C
Q3-D
Q6-D
Q11-A
Q12-B
Q17-D
Q21-D
Q24-C
A26-C
Q38-B
plz I NEED HELP

 

[princessnoor]

i don't understand your question. what is for and what is x2/4(b-x)2

thts the answer

 

[Kamihus]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w11_qp_11.pdf

Q13, i don't how to get this, i have got volume as 60 cm3, how is it 30 cm3

Q13? You sure?

 

[ziremm]

hello guys can you please help with these questions ASAP :/
q1,4,9,19,23,39,36,33
thanks a lot

question paper: http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w07_qp_1.pdf

mark scheme : http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w07_ms_1.pdf

 

[MiniSacBall]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s07_qp_1.pdf

Q9, Explain plz


http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s10_qp_11.pdf
Q13

Also, how does it hydrochloric acid behave as acid when it is added to NaCl,
And H2SO4 conc. is used for hydrolosis or dehydration, and what about NaOH,

I need urgent help !

I am really sorry to tag you but i have an urgent stituation here, i have hardly 5 minutes before i have go offline
Suchal Riaz ZaqZainab

 

[ZaqZainab]

thts the answer

what do you mean x2?

 

[ZaqZainab]

Q13? You sure?

i am guessing he means 14

 

[SIstudy]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w11_qp_12.pdf
Q9 (D)
I could make out tht glucose and fructose are structural isomers so option A and C is ruled out but cant understand how osmotic pressure is affected?

 

[princessnoor]

i don't understand your question. what is for and what is x2/4(b-x)2

here u go question 11 ppr http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w02_qp_1.pdf
answer is D

 

[MiniSacBall]

Q13? You sure?

Sorry it is
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s11_qp_11.pdf

Q13, i don't how to get this, i have got volume as 60 cm3, how is it 30 cm3
M/J 2011

 

[princessnoor]

what do you mean x2?

http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w02_qp_1.pdf
question 11 answer is D

 

[AhsanAfzal]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w09_qp_11.pdf
Q18 hydrocarbons are present in catalytic converters??????
and someone pls explain Q19 too