Chemistry: Post your doubts here!

[areeba240]

http://pastpapers.papacambridge.com.../Chemistry (9701)/2016 Jun/9701_s16_qp_42.pdf
qtn 5b(ii) can anyone explain me this in detail?

 

[areeba240]

plzz explain ??

 

[Mathemagical]

http://pastpapers.papacambridge.com/Cambridge International Examinations (CIE)/AS and A Level/Chemistry (9701)/2016 Jun/9701_s16_qp_42.pdf
qtn 5b(ii) can anyone explain me this in detail?

Gibbs free energy = H - TS
S = (H-G)/T *1000

You multiply by 1000 because the unit for S is J/Kmol, while the units for H and G are kJ.
Hence, the answer is 14.1.

 

[areeba240]

Gibbs free energy = H - TS
S = (H-G)/T *1000

You multiply by 1000 because the unit for S is J/Kmol, while the units for H and G are kJ.
Hence, the answer is 14.1.

can u plzz explain the (iii) as well

 

[Mathemagical]

can u plzz explain the (iii) as well

Entropy is a measure of disorder.

For I, 1 mole of the complex is formed from 5 moles of solute. Hence, there is a decrease in entropy.

For II, 1 mole of the complex is formed from 3 moles of solute. This means there is an increase in entropy (disorder), because fewer moles of solute forms the complex.

 

[Thought blocker]

https://www.xtremepapers.com/community/threads/physics-component-marks-for-a-level-only.46161/

 

[krishnapatelzz]

View attachment 61578
5(ii) pzz help

5 a (ii) ??? should i solve or u had doubt in 5 b (ii)

 

[krishnapatelzz]

https://www.xtremepapers.com/community/threads/suggestion-for-9709-mechanics-p4-5.46187/
mechanics !!!!!!!!!

 

[Nourhan95]

Salam, can I please ask if there's such a thing as Dupont in chemistry? It has symbols like R134a and we have to figure out which compound that is. Any clues?

 

[Mari_am]

Pls could someone send me notes on lattice energy,I would appreciate it

 

[Thought blocker]

Pls could someone send me notes on lattice energy,I would appreciate it

It was on XPC :https://www.dropbox.com/s/26bg9lzcgl8kdbm/chapter 20_ lattice energy.pdf?dl=0

 

[Mari_am]

There is an error with the file

 

[krishnapatelzz]

Can someone explain for question d ??

 

[drowning-in-studies]

View attachment 61644View attachment 61645View attachment 61644 View attachment 61645 Can someone explain for question d ??

This is the AS/A level thread but anyway,
we know the filtrate contains aluminium sulfate
and aq silver nitrate is the test for Cl, Br, I
so no ppt/ reaction for Al2(SO4)3 (since the halide ions aren't present in here)

 

[teachyourself]

https://www.xtremepapers.com/commun...yub-alevel-books-for-organic-chemistry.46206/

https://www.youtube.com/results?search_query=a+levels+chemistry
https://www.khanacademy.org/
https://www.youtube.com/user/MrERintoul
https://www.xtremepapers.com/community/threads/schaums-outline-torrent.46201/ -- also use schaums outline for extra practice and step by step solutions
https://thepiratebay.org/torrent/8181452/Math_Tutor_DVD_-_Chemistry_1_(Vol._3__4)

 

[student2]

Cn dere b H- bonds b/w Ch3CH2CH2NH2 molecules? Lyk the +ve H of 1 molecue to a -ve N of a diff molecule?

 

[Thought blocker]

Cn dere b H- bonds b/w Ch3CH2CH2NH2 molecules? Lyk the +ve H of 1 molecue to a -ve N of a diff molecule?

Yes it can have. Strong electronegative element N is present in other propanamine that can form H bonds with hydrogen present in the other propanamine.

 

[student2]

ok. cn sm1 tell me if the chem P5 pprs hv a format which does nt hv planning experiments lyk b4? I dnt see ques lyk tht in recent yrs so wondering if it's chnged?

 

[krishnapatelzz]

ok. cn sm1 tell me if the chem P5 pprs hv a format which does nt hv planning experiments lyk b4? I dnt see ques lyk tht in recent yrs so wondering if it's chnged?

read syllabus .. planning is a part of the paper

 

[Dharyl]

hi all, can somebody help me, i am looking for a revision book for ATP o level chemistry sylab:5070, thanks