Chemistry P1 Challenging Questions Preparation

[Geistpanzer]

Considering the difficulty of p1 physics this year I think it's safe to say that CIE will probably increase the difficulty level of both Chemistry and Biology more than the papers from the previous decade.

If you guys have any tips or difficult/challenging question banks for practice or what, just post it here and we'll discuss. Hopefully it'll be beneficial for all of us.

 

[Aries_95]

Yeah...agree with you...they have increased the difficulty level of the papers, keeping in mind Chem Paper 42 (Was the hardest in history probably )...they will increase the difficulty level of paper one.
Tips, notes anyone?
I have for organic chemistry.

 

[cute97]

Anyone please
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w11_qp_11.pdf
Q9, Q20 and what is meant by 6-membered rings??, and Q25
Thanks in advance

 

[queen of the legend]

Anyone please
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w11_qp_11.pdf
Q9, Q20 and what is meant by 6-membered rings??, and Q25
Thanks in advance

q9 i cudnt get thre right answer

q20 :
you get 3 hydroxy groups ( one is already present) and teo from the reaction between cold KMnO4 on alkene producing a diol.
number of 6 membered ring remaining means how many rings now remian in the whole structure consisting of 6 bonded elemnets. since hot reagent oxidizes the alcohols...the remaining rings are 2 which will have no effect (i guess this is what is meant)

q25:
ok this is kinda easy ... write a simplified equation ethanol --------> ethanioc acid
Mr: 46 60
so 2.76 ethanol yield how musch ethanioc acid 2.76 x

cross multiple you will get 3.6 g the yield is 75% hence 3.6 x 0.75 = 2.7g

 

[cute97]

q9 i cudnt get thre right answer

q20 :
you get 3 hydroxy groups ( one is already present) and teo from the reaction between cold KMnO4 on alkene producing a diol.
number of 6 membered ring remaining means how many rings now remian in the whole structure consisting of 6 bonded elemnets. since hot reagent oxidizes the alcohols...the remaining rings are 2 which will have no effect (i guess this is what is meant)

q25:
ok this is kinda easy ... write a simplified equation ethanol --------> ethanioc acid
Mr: 46 60
so 2.76 ethanol yield how musch ethanioc acid 2.76 x

cross multiple you will get 3.6 g the yield is 75% hence 3.6 x 0.75 = 2.7g

thank you
i got this answer for Q9
9. You'll have to draw a chart showing the initial moles, change in moles and equilibrium moles. Leave out Ag because it's a solid.

 

[cute97]

can u help me with this plz Q9 we dont knw the fuel then how we will find number of moles
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w10_qp_11.pdf
Q9

 

[queen of the legend]

can u help me with this plz Q9 we dont knw the fuel then how we will find number of moles
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w10_qp_11.pdf
Q9

use mc x delta T
200 x (66-18) x 4.2 = 40320

ok they tell u that 45% is absorbed by water ...so 40320 energy is actually only 45 % of the energy already relased ..so to calculate 100 % which is released u do a reverese process divide 40320 by 0.45 = 89600 .......then they ask for (per gram of fuel) so divide this by 1.6g u'll get the answer

 

[Sara syed]

in s10 qp13 question 30 what r the three alkenes that btan2 ol can produce
on dehydration i know its's but1-ene and but2-ene what is the third one?

 

[cute97]

use mc x delta T
200 x (66-18) x 4.2 = 40320

ok they tell u that 45% is absorbed by water ...so 40320 energy is actually only 45 % of the energy already relased ..so to calculate 100 % which is released u do a reverese process divide 40320 by 0.45 = 89600 .......then they ask for (per gram of fuel) so divide this by 1.6g u'll get the answer

thank youuu very muchi got one more doubt can u try it plz
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s11_qp_12.pdf
Q19

 

[queen of the legend]

in s10 qp13 question 30 what r the three alkenes that btan2 ol can produce
on dehydration i know its's but1-ene and but2-ene what is the third one?

the OH can be attached on either side considerign that carbon no.2 so a third one results but-2-ene as well

 

[Sara syed]

s11 qp 11 question is a chalenging question pls post the working if u r able workout and get D as the answer

 

[queen of the legend]

thank youuu very muchi got one more doubt can u try it plz
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s11_qp_12.pdf
Q19

the HClO ....ok we know that oxugen has -2 ox.state and hydrogen must be +1 .....to find for chlorine use this -2 +1 +x = 0 since there is no overall charge n the molecule so x = +1 hence H and Cl have similar ox.state

 

[cute97]

the HClO ....ok we know that oxugen has -2 ox.state and hydrogen must be +1 .....to find for chlorine use this -2 +1 +x = 0 since there is no overall charge n the molecule so x = +1 hence H and Cl have similar ox.state

but also for Mg(OH)2 i got the oxidation state same for hydrogen and Mg that is +2 and for oxygen -2 sooo this one is also correct ??

 

[queen of the legend]

but also for Mg(OH)2 i got the oxidation state same for hydrogen and Mg that is +2 and for oxygen -2 sooo this one is also correct ??

no dear .... Mg is +2 oxygen is -2 and one hydrogen or each hydrogen is +1

to calculate ox. state of hydrogen +2 + (-2 x 2 ) + 2x =0 2x is 2 hydrogen
so x = +1

 

[cute97]

no dear .... Mg is +2 oxygen is -2 and one hydrogen or each hydrogen is +1

to calculate ox. state of hydrogen +2 + (-2 x 2 ) + 2x =0 2x is 2 hydrogen
so x = +1

ohhh okaayy thank you very much wish u best of luck

 

[fishcook]

http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s11_qp_12.pdf
How would you do question 33? :S
Please help

 

[1ajia1]

33 The conversion of graphite into diamond is an endothermic reaction (ΔH = +3 kJ mol–1).
C(graphite) → C(diamond)
Which statements are correct?1 The enthalpy change of atomisation of diamond is smaller than that of graphite.
2 The bond energy of the C–C bonds in graphite is greater than that in diamond.
3 The enthalpy change of combustion of diamond is greater than that of graphite.
http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w07_qp_1.pdf(mcq 33)

http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w09_qp_11.pdf
(mcq 28 and 28)
someone please help, I will be utterly grateful
thank you.

 

[1ajia1]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s11_qp_12.pdf
How would you do question 33? :S
Please help

OPTION 1 is right because density/ mass gives you 1/ volume.
Option 2 is wrong so 3 is also wrong and the only remaining answer is D

 

[fishcook]

OPTION 1 is right because density/ mass gives you 1/ volume.
Option 2 is wrong so 3 is also wrong and the only remaining answer is D

How do you know that density/ mass is 1/volume?
And why is 2 wrong?

 

[1ajia1]

How do you know that density/ mass is 1/volume?
And why is 2 wrong?

density =mass/ volume so density/ mass is 1/ volume
2 is wrong because PV=moles ( n ) RT and while the option is PV=M(molar mass)RT