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Chemistry: Post your doubts here!

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Hello. I need help in calculations of the titration in paper 3!!!!!!!!!!
Can anyone post solved paper 3s or any help pleaasee???
 
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yeah, you're right. it is 40. Then, I have no idea why it says 130 as maximum marks for AS.
Max marks for P3 are 40 :)

The total marks for the syllabus are indeed 140.. but i think the weightage of P3 is 30 marks...

Look at:

2wRB8.jpg


23% at AS Level for P3.. That's only possible if P3 Marks are taken to be 30.

30/(130) *100 = 23%

40/140*100 = 28% .. which is wrong.

I can't say anything else.. lol
 
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The total marks for the syllabus are indeed 140.. but i think the weightage of P3 is 30 marks...

Look at:

2wRB8.jpg


23% at AS Level for P3.. That's only possible if P3 Marks are taken to be 30.

30/(130) *100 = 23%

40/140*100 = 28% .. which is wrong.

I can't say anything else.. lol
Go Get A life Bro :p lol :D
 
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do anyone have chemactive a level chemistry worksheets please upload it the site is down for quite a time i wanted those worksheets. and if some has chemistry mark schemes for all past papers compiled please upload
 
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O/N 11/12 question 3
Can anyone who is good in chemistry solve this?
Use of the Data Booklet is relevant to this question.
From which particle is the removal of an electron the most difficult?
A Cl- (g) B F- (g) C K+ (g) D Na+ (g)
 
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do anyone have chemactive a level chemistry worksheets please upload it the site is down for quite a time i wanted those worksheets. and if some has chemistry mark schemes for all past papers compiled please upload
Can you answer the question posted above please?
 
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O/N 11/12 question 3
Can anyone who is good in chemistry solve this?
Use of the Data Booklet is relevant to this question.
From which particle is the removal of an electron the most difficult?
A Cl- (g) B F- (g) C K+ (g) D Na+ (g)
When an electron is removed from an atom, the nucleus has a stronger hold on the remaining electrons. That is why it is difficult to remove an electron when one has already been removed. This leaves us with option C and D to choose from.
Removal of an electron in the last two cases mentioned involves the second Ionisation Energy.
Use the Data Booklet to check the energy for each, K+ has 3070 while Na+ has 4560 kJ/mol. More energy means it is more difficult to remove an electron.
 
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When an electron is removed from an atom, the nucleus has a stronger hold on the remaining electrons. That is why it is difficult to remove an electron when one has already been removed. This leaves us with option C and D to choose from.
Removal of an electron in the last two cases mentioned involves the second Ionisation Energy.
Use the Data Booklet to check the energy for each, K+ has 3070 while Na+ has 4560 kJ/mol. More energy means it is more difficult to remove an electron.
Untitled.png
Can you answer this also please? Its from the same year and variant is 13.
 
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Sorry but I'm rather unsure about this one yet.


It's okay, with exams coming up that happens too often :p
No, they can be aqueous too.
hahahah thats true , seriously I never felt such pressure before. I knew this too :p They can be aqueous too :p
 
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i cant do most of the questions on aldehydes,ketones,carboxylic acids, alcohols and esters on P1 and P2. My problem is that they ask for substances i've never seen. plz tell me an easy way of solving questions like these.
 
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in a equation how do we know which reactant on change in concentration has no effect on the rate of reaction
eg:
CH3CH=CH2 + I2 -------> CH3CHICH2I

PLZ i need to know its important
 
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