Chemistry: Post your doubts here!

[..sacrifice4Revenge..]

But the answer is D
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s07_ms_1.pdf

 

[GCE As and a level]

10-A is non-polar. In D it is cancelled out. C has less difference as both are negative. B most as one negative, one positive.
16-Forms NaClO3, with hot. NaClO with cold.
23-Add H and Br to the double bonds
37-CH3CH(double bond)-CH2 so 3 can't be formed.

ZaqZainab
Here is Q37

 

[Youssef Tawil]

Thnx for ........

Hahahaha inshallah we will do well

 

[GCE As and a level]

Every one can do mistakes
Especially with this great SUBJECT

 

[..sacrifice4Revenge..]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w11_qp_12.pdf

Q26 (B)
idk wht im doin wrong I tried it many times, but my answer isn't in the options :$ :/

ethanol-ethanal
46:44
2.30-x
x=2.20g

2.20 X70/100
=1.54g

 

[GCE As and a level]

Hahahaha inshallah we will do well

Inshallah
Just let us to pray for each other

 

[..sacrifice4Revenge..]

Every one can do mistakes
Especially with this great SUBJECT

yeah right, 'Chemistry the Great'

 

[kingo44]

chemidtry iam aliveeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

 

[GCE As and a level]

chemidtry iam aliveeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

I think that we are only physically aliveeeeeeeeeeee

 

[..sacrifice4Revenge..]

chemidtry iam aliveeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

No shit sherlock!

 

[GCE As and a level]

..sacrifice4Revenge.. http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s12_qp_12.pdf
Q20
Q25

 

[unique111]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s07_qp_1.pdf
Q12- How is B even possible?
40-How does carboxylic acid react with an ester

Q12) https://www.xtremepapers.com/community/threads/chemistry-mcq-thread.7567/page-2#post-98170
Q40) my mind is boggled! :s

 

[..sacrifice4Revenge..]

..sacrifice4Revenge.. http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s12_qp_12.pdf
Q20

ok,
ive went over this question thrice, doing it the wrong way everytime but with the correct answer, idk how
now had to do it correctly,
ok so the products are
propanol, and sodium ethanoate
calculate their MR
60 and 82

now mass of propanol
60/82 X100
= 42.3%
so C

 

[MYLORD]

Friends i dont know what to do enthalpy questions
It sticks to my head like a leech

 

[..sacrifice4Revenge..]

..sacrifice4Revenge.. http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s12_qp_12.pdf
Q20
Q25

25

it is an activated complex involving 5bonds of carbon.
so has to be C or D
now, in D. C has a negative electronegativity charge which is wrong
so is C,which is correct in all ways

 

[..sacrifice4Revenge..]

Friends i dont know what to do enthalpy questions
It sticks to my head like a leech

use this


If given only heat of combustions, then use heat of combustion of reactants - heat of formation of products

If given only heat of formation, then use heat of formation of products - heat of formation of reactants

If given only bond energy, BE of reactants - BE of products

 

[MYLORD]

use this


If given only heat of combustions, then use heat of combustion of reactants - heat of formation of products

If given only heat of formation, then use heat of formation of products - heat of formation of reactants

If given only bond energy, BE of reactants - BE of products

thnx bro

 

[unique111]

Q12) https://www.xtremepapers.com/community/threads/chemistry-mcq-thread.7567/page-2#post-98170
Q40) my mind is boggled! :s

Q 40) now that I think of it, the question is asking for ester hydrolysis. It is hydrolysed by water or by dilute acids. The only acid here is ethanoic acid, despite being a weak acid, it is still an acid. :/

 

[AhsanAfzal]

http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s10_qp_11.pdf
Q19 H3PO4 is weak acid, then why is the answer A?

 

[GCE As and a level]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w12_qp_11.pdf
Q6
q11
Q17
q21
Q24
Q26
Q38