• We need your support!

    We are currently struggling to cover the operational costs of Xtremepapers, as a result we might have to shut this website down. Please donate if we have helped you and help make a difference in other students' lives!
    Click here to Donate Now (View Announcement)

Chemistry: Post your doubts here!

knowitall10

knowitall10

Messages
2,865
Reaction score
13,723
Points
523
applepie1996 said:
HA HA xD
everything helps ............whether its paper 5 or 4 :)
besides its fine :D you can start practicing paper 4 after paper 5 :)
you have a lot of time after that :)
in the end its your choice (y)
Click to expand...
Yeah.. i know but after making an account here, i realized i'm actually answers to my questions by myself cuz many questions here were the ones that i always had.. but many of them are also Paper 5 questions.. my theory is not that thorough.. and i need something to boost my enthusiasm the way it did when we discussed P5's. I'm scared i wont be able to do good...:(
How do you manage your time equally? Any ideas?
 
applepie1996

applepie1996

Messages
1,601
Reaction score
553
Points
123
knowitall10 said:
Yeah.. i know but after making an account here, i realized i'm actually answers to my questions by myself cuz many questions here were the ones that i always had.. but many of them are also Paper 5 questions.. my theory is not that thorough.. and i need something to boost my enthusiasm the way it did when we discussed P5's. I'm scared i wont be able to do good...:(
How do you manage your time equally? Any ideas?
Click to expand...
first you tell me what subjects you take :)
and then i will help you manage out :)
its not that difficult to handle when you have everything sorted out :)
InshaAllah you will do good (y)
so i can know what exams you have on what day :)
 
M

MaxStudentALevel

Messages
199
Reaction score
138
Points
43
knowitall10 said:
Yeah.. i know but after making an account here, i realized i'm actually answers to my questions by myself cuz many questions here were the ones that i always had.. but many of them are also Paper 5 questions.. my theory is not that thorough.. and i need something to boost my enthusiasm the way it did when we discussed P5's. I'm scared i wont be able to do good...:(
How do you manage your time equally? Any ideas?
Click to expand...

BEST way is to just go through papers 2007-2012 and if you don't have time
-just 2012-2010 is sufficient!
-Mark problem areas and review those from the book

ALSO please make a separate Chem P4 thread and we can start discussions there as well!
 
M

MaxStudentALevel

Messages
199
Reaction score
138
Points
43
knowitall10 said:
Yeah.. i know but after making an account here, i realized i'm actually answers to my questions by myself cuz many questions here were the ones that i always had.. but many of them are also Paper 5 questions.. my theory is not that thorough.. and i need something to boost my enthusiasm the way it did when we discussed P5's. I'm scared i wont be able to do good...:(
How do you manage your time equally? Any ideas?
Click to expand...

Also, are you giving Physics?
 
M

MaxStudentALevel

Messages
199
Reaction score
138
Points
43
applepie1996 said:
first you tell me what subjects you take :)
and then i will help you manage out :)
its not that difficult to handle when you have everything sorted out :)
InshaAllah you will do good (y)
so i can know what exams you have on what day :)
Click to expand...

That was very kind of you! I hardly see people like that! You're so sweet, may Allah make ou successful in life!
 
T

TSZ

Messages
215
Reaction score
29
Points
38
Hey, I have some P5 problems.
my first question is from May june 12 ppr 51. In Q1 part (c), can any one explain, in detail (as these questions always get the best of me), how to produce a saturated solution of concentration 1.39 moldm-3. Then I can handle the rest :)
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s12_qp_51.pdf
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s12_ms_51.pdf

My next problem is in Paper 51 of Nov 12. What I don't get is that in Q1 part (e), how will we use the results to reach a conclusion. The mark scheme says to calculate moles of Pb and O, but in metallic reduction by H2, i think water is produced and not O2, then how will we calculate moles of Oxygen. Thank you in advance

http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w12_qp_51.pdf
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w12_ms_51.pdf​
 
M

MaxStudentALevel

Messages
199
Reaction score
138
Points
43
TSZ said:
Hey, I have some P5 problems.
my first question is from May june 12 ppr 51. In Q1 part (c), can any one explain, in detail (as these questions always get the best of me), how to produce a saturated solution of concentration 1.39 moldm-3. Then I can handle the rest :)
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s12_qp_51.pdf
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s12_ms_51.pdf

My next problem is in Paper 51 of Nov 12. What I don't get is that in Q1 part (e), how will we use the results to reach a conclusion. The mark scheme says to calculate moles of Pb and O, but in metallic reduction by H2, i think water is produced and not O2, then how will we calculate moles of Oxygen. Thank you in advance

http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w12_qp_51.pdf
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w12_ms_51.pdf​
Click to expand...

For saturated solutions usually the following method is used:
-Add fixed masses (eg 2g) to a fixed volume of water (eg) 100cm3
-Add one sample of fixed mass, stir and see if any crystals (undies solved) appear.
-If they do, don't add any further mass and proceed to step (2)
-If they don't, add further increments of masses and stir between each to see if any appears and stop when solid crystals appear.

(2) now filter the solution using a beaker and filter paper. The filtrate is the saturated solution!!
 
knowitall10

knowitall10

Messages
2,865
Reaction score
13,723
Points
523
applepie1996 said:
first you tell me what subjects you take :)
and then i will help you manage out :)
its not that difficult to handle when you have everything sorted out :)
InshaAllah you will do good (y)
so i can know what exams you have on what day :)
Click to expand...
Oh alright.. thanks a lot! Jazaki Allahu Khair!!!
Well i take bio, chem and math(edexcel). Its just chemistry i need help with actually...But thanks a lot for willing to help..May Allah Succeed all of us in this life and in the Hereafer--aameen--.
You too MaxStudentALevels! Thanks a lot!
Jazakum Allahu khair!:D
 
M

MaxStudentALevel

Messages
199
Reaction score
138
Points
43
TSZ said:
Hey, I have some P5 problems.
my first question is from May june 12 ppr 51. In Q1 part (c), can any one explain, in detail (as these questions always get the best of me), how to produce a saturated solution of concentration 1.39 moldm-3. Then I can handle the rest :)
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s12_qp_51.pdf
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s12_ms_51.pdf

My next problem is in Paper 51 of Nov 12. What I don't get is that in Q1 part (e), how will we use the results to reach a conclusion. The mark scheme says to calculate moles of Pb and O, but in metallic reduction by H2, i think water is produced and not O2, then how will we calculate moles of Oxygen. Thank you in advance

http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w12_qp_51.pdf
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w12_ms_51.pdf​
Click to expand...

Decided to read the paper: I don't think that method is applied here.
Here, you'd calculate number of moles needed in 250 cm3 to make 1.39moldm-3
Using the unity method you should be able to do that.
---> then use moles to find mass needed.
----> NOW what you do is dissolve the solid mass calculated into less than 250 cm3 (like 100) and pour it into a volumetric flask.
----> now using a wash bottle for accuracy fill it up to 250cm3 mark! And that's your solution
----> prepare further concentrations by serial dilution or the other method with same total volumes
 
applepie1996

applepie1996

Messages
1,601
Reaction score
553
Points
123
knowitall10 said:
Oh alright.. thanks a lot! Jazaki Allahu Khair!!!
Well i take bio, chem and math(edexcel). Its just chemistry i need help with actually...But thanks a lot for willing to help..May Allah Succeed all of us in this life and in the Hereafer--aameen--.
You too MaxStudentALevels! Thanks a lot!
Jazakum Allahu khair!:D
Click to expand...
JazkAllah :D and I pray and hope the same for you :D
well .......that's not too bad :) you are lucky you don't take physics :)
okaiy if you are done with chem paper 5 now just leave it till the day before the exam
and start studying for chemistry paper 4 :)
read the text book thoroughly and for the application part i would recommend that you study from the site chem guide :)
now bio i don't know :S as i don't take it :/
i am sorry i can't help .....
but what i can tell you is that first you finish chemistry COMPLETELY forget past papers now
study the book and the syllabus first .............finish the whole portion in like 3 days
and then start bio and keep revising chem
and as for math its toooooo far away now sooooooooo don't worry :D
just do one past paper every alternate days to keep in touch :D
ooh and if you ever have any doubt in chem you are always free to ask me :D
InshaAllah i will try my best to help you :D
 
M

MaxStudentALevel

Messages
199
Reaction score
138
Points
43
knowitall10 said:
Oh alright.. thanks a lot! Jazaki Allahu Khair!!!
Well i take bio, chem and math(edexcel). Its just chemistry i need help with actually...But thanks a lot for willing to help..May Allah Succeed all of us in this life and in the Hereafer--aameen--.
You too MaxStudentALevels! Thanks a lot!
Jazakum Allahu khair!:D
Click to expand...

I highly suggest you take time to make a chemP4 thread so we can use that! Like xhizors made separate for P5 it'll be much easier? Tag us all?
 
knowitall10

knowitall10

Messages
2,865
Reaction score
13,723
Points
523
applepie1996 said:
JazkAllah :D and I pray and hope the same for you :D
well .......that's not too bad :) you are lucky you don't take physics :)
okaiy if you are done with chem paper 5 now just leave it till the day before the exam
and start studying for chemistry paper 4 :)
read the text book thoroughly and for the application part i would recommend that you study from the site chem guide :)
now bio i don't know :S as i don't take it :/
i am sorry i can't help .....
but what i can tell you is that first you finish chemistry COMPLETELY forget past papers now
study the book and the syllabus first .............finish the whole portion in like 3 days
and then start bio and keep revising chem
and as for math its toooooo far away now sooooooooo don't worry :D
just do one past paper every alternate days to keep in touch :D
ooh and if you ever have any doubt in chem you are always free to ask me :D
InshaAllah i will try my best to help you :D
Click to expand...
Wow.. Jazaki Allahu Khair! May Allah bless you!
Nice idea... thanks a lot...
 
Wanderer

Wanderer

Messages
64
Reaction score
25
Points
8
Can you guys also suggest a sensible diagram for NOV10/53 q1
Should we use a divider flask?What sort of internal separation device will be used here to separate H2O2 and the catalyst??
 
T

TSZ

Messages
215
Reaction score
29
Points
38
MaxStudentALevel said:
Decided to read the paper: I don't think that method is applied here.
Here, you'd calculate number of moles needed in 250 cm3 to make 1.39moldm-3
Using the unity method you should be able to do that.
---> then use moles to find mass needed.
----> NOW what you do is dissolve the solid mass calculated into less than 250 cm3 (like 100) and pour it into a volumetric flask.
----> now using a wash bottle for accuracy fill it up to 250cm3 mark! And that's your solution
----> prepare further concentrations by serial dilution or the other method with same total volumes
Click to expand...
Thank you for your response. I do have some queries regarding this process. 1. the moles needed are 0.3475. Now I multiply it with Mr of CuSO4 which will be 159.5 or with Mr of CuSO4.5H20 which will be 249.6.....2. When I will take the mass required and put it in 100cm^3 water, won't the water saturate before dissolving all of it, since the mass is for 250 cm^3? Thank you again for your help :)
 
You must log in or register to reply here.
Top