Chemistry: Post your doubts here!

[anastasia grey113]

what does subs mean? lol

u took 4 subjects?

 

[haithsoul]

u took 4 subjects?

yes yes

 

[anastasia grey113]

E cell for VO+2 is +1.00 volt and for iron its +0.77. since e cell for VO is more so its redues so E cell is 1-0.77=0.23 which is less than 0.3 so not happening

shouldnt it be like 0.77-1?
becuz like the E for VO2+ sure is 1.00 but in it VO2+ is being oxidised to V2+ so shouldnt it be changed to -1?

 

[anastasia grey113]

yes yes

wowww MA

 

[haithsoul]

shouldnt it be like 0.77-1?
becuz like the E for VO2+ sure is 1.00 but in it VO2+ is being oxidised to V2+ so shouldnt it be changed to -1?

yes you are right my bad.
and yeah 4 subject sucking the life outta me

 

[SohaibButt]

Also Holmes this is actually the correct explanation
well you can only have two isomers
cis and trans
and for the cis isomer, there will be two optical isomers since there is also a bidentate ligand present
THIS IS TRANS
View attachment 63567
THE ONES BELOW ARE BOTH CIS AND MIRROR IMAGES OF EACH OTHER...THE LINE IN BETWEEN IS THE MIRROR
THIS KIND OF ISOMERISM IS ONLY POSSIBLE WHEN BIDENTATE LIGANDS ARE ALSO PRESENT
View attachment 63568

Thanks

 

[Tauqir_hamed]

anyone knows material for 33?

 

[Fardeen3342]

well the two cis shown are optical isomers or mirror images of each other
Fardeen3342

YE I REALIZED THAT

 

[ujjwal jha]

do anyone have march 2018 chemistry paper 4 question paper in soft copy . please help. it would be kind of you

 

[Zaki ali asghar]

can someone tell what's in syllabus related to DNA? just the hydrogen bonding for replication?

 

[anastasia grey113]

can someone tell what's in syllabus related to DNA? just the hydrogen bonding for replication?

yh
and the structure is often asked for so know the which base pairs with which

 

[Holmes]

9701/43/nov 2017
1-How am I supposed to know the splitting patterns without the NMR spectrum given?
2-In column 1 is it the number of hydrogen on adjacent carbon or the carbon which is under study?

 

[anastasia grey113]

View attachment 63578
9701/43/nov 2017
1-How am I supposed to know the splitting patterns without the NMR spectrum given?
2-In column 1 is it the number of hydrogen on adjacent carbon or the carbon which is under study?

well the values in ppm are given so u dont need the spectrum since u already have the values
its the on the C studied

 

[Fardeen3342]

if anyone has fm 2018 just like they did for bio please post it . thank you

 

[Zaki ali asghar]

does someone have all organic reactions compiled?

 

[Fardeen3342]

does someone have all organic reactions compiled?

 

[Fardeen3342]

second equation welp

 

[Hajera]

Need help with a Q5 (c) from Oct/Nov 2017 paper 41

Why is there no addition of HCl with the double bond?

 

[Zaki ali asghar]

Need help with a Q5 (c) from Oct/Nov 2017 paper 41View attachment 63581 View attachment 63582
Why is there no addition of HCl with the double bond?

for that you need concentrated hcl and at rtp

 

[Hajera]

for that you need concentrated hcl and at rtp

but look at the 1st row. when excess Br2 (aq) is reacted with the molecule, addition does occur. even though they didnt mention whether it is conc or at rtp.