Chemistry: Post your doubts here!

[nehaoscar]

No C can only form four bonds
two already there due to double bond , one is attached to other carbon nd last bond to O
draw the structure of it if ur confused

But then it only shows single bonds in the ring...

Where are the double bonds inside the ring?

 

[fantastic girl]

Halogenoalkanes undergo Elimination/Dehydration and Nucleophilic substitution. When adding KOH in ethanol (reflux), it forms alkene (elimination reaction) , not NaOH, with NaOH in water (reflux) it forms alcohol which is Nucleophilic substitution

oh sorry i meant elimination **
thanks for correcting bro
nehaoscar sorry for my error....i hve been typing too much

 

[Maayee]

http://studyguide.pk/Past Papers/CIE/International A And AS Level/9701 - Chemistry/9701_w07_qp_1.pdf
in question 4, why is it C and not D?

 

[fantastic girl]

But then it only shows single bonds in the ring...
View attachment 54510
Where are the double bonds inside the ring?

hey no
the benzene ring has three double bonds within it

 

[fantastic girl]

But then it only shows single bonds in the ring...
View attachment 54510
Where are the double bonds inside the ring?

that is how a benzene ring luks

 

[nehaoscar]

hey no
the benzene ring has three double bonds within it

But they don't show it... so how do you know it has??

Like this is a different question where they show the double bonds in one ring and then the other rings have the chiral centres marked
So if you consider the double bonds in this one in the rings you'd get the answer wrong

 

[fantastic girl]

http://studyguide.pk/Past Papers/CIE/International A And AS Level/9701 - Chemistry/9701_w07_qp_1.pdf
in question 4, why is it C and not D?

the electrons get removed frm the outer most shell
nd looking at the graph we can say 2 electrons are removed frm the outer most shell bcaz u can see there is a huge difference between the third point nd 2nd point on the graph which means 3rd electron is removed frm a shell closer to the nucleus that is the 2nd last shell
so the outer shell has two electrons only nd this happens only in a grp 2 element

 

[nehaoscar]

View attachment 54511
that is how a benzene ring luks

Oh i think i get you!
Is it that if the ring has a circle drawn inside it, then it's a benzene ring with 3 double bonds and if it doesn't have a circle it doesn't have double bonds unless specified??

 

[fantastic girl]

But they don't show it... so how do you know it has??

Like this is a different question where they show the double bonds in one ring and then the other rings have the chiral centres marked
So if you consider the double bonds in this one in the rings you'd get the answer wrong
View attachment 54513

u hve got me wrong :/
u see there is a ring in the diagram of the question u asked ---- u shud know the structure of benzene ring
in this question where is the ring ??
idk if i studied this in AS or A2 becaz iam giving Alevel in this session :/

 

[Maayee]

the electrons get removed frm the outer most shell
nd looking at the graph we can say 2 electrons are removed frm the outer most shell bcaz u can see there is a huge difference between the third point nd 2nd point on the graph which means 3rd electron is removed frm a shell closer to the nucleus that is the 2nd last shell
so the outer shell has two electrons only nd this happens only in a grp 2 element

ahhh ok, thank you soo much

 

[hassannouman]

oh sorry i meant elimination **
thanks for correcting bro
nehaoscar sorry for my error....i hve been typing too much

no problem just making sure that correct information is passed

 

[fantastic girl]

Oh i think i get you!
Is it that if the ring has a circle drawn inside it, then it's a benzene ring with 3 double bonds and if it doesn't have a circle it doesn't have double bonds unless specified??

yes ur ryt
the circle is the ring itself

 

[fantastic girl]

ahhh ok, thank you soo much

most welcome

 

[nehaoscar]

yes ur ryt
the circle is the ring itself

Yayy! Thankyou!
Could you also please if possible look at some of the previous questions I have posted which have not been answered from the end of page 681 on this thread onwards?

 

[fantastic girl]

Yayy! Thankyou!
Could you also please if possible look at some of the previous questions I have posted which have not been answered from the end of page 681 on this thread onwards?

lol
No problem
yea sure i will check in a while In shaa Allah!

 

[nehaoscar]

Why not A?

 

[nehaoscar]

Why not C?

 

[Metanoia]

View attachment 54514
Why not A?

NaF is expected to have a higher mp/bp than KCl, as mp/bp is inversely proportional to the ionic radii.

In other words, the larger the ions, the lower the mp/bp.

Edited parts in yellow.

 

[hassannouman]

View attachment 54517
Why not C?

Ketone is present in CH3CH2OCOCH3, secondary alcohol oxidise to form ketone with H+/K2Cr2O7 (Oxidation) , It's not esterification as carboxylic acid is not used.

 

[nehaoscar]

Ketone is present in CH3CH2OCOCH3, secondary alcohol oxidise to form ketone with H+/K2Cr2O7 (Oxidation) , It's not esterification as ester is not present

Doesn't the OCO represent an ester?
And also the question says that ethyl ethanoate is produced