Chemistry: Post your doubts here!

[Haya Ahmed]

Option D has Propane is Liquid state which is Gas

how did you know ... maybe it can be liquid .. why are you sure that it is gas

 

[Mohammed salik]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s11_qp_12.pdf


People please help me ..

Q8
Q22
Q29
Q30
Q38

Q29:- (D) Because Cold one Breaks double Bond and Forms Diol (two OH groups added ) giving two chiral centers. And with Hot KMnO4 it disrupts the double bind completely which causes this compound to lose one chiral center!

 

[Mohammed salik]

First 5 alkanes are gas !

how did you know ... maybe it can be liquid .. why are you sure that it is gas

 

[Haya Ahmed]

Q22:-(C) bcz best yeild only in adddition reaction, which is with alcohol!

Why not B ..

 

[Mohammed salik]

Why not B ..

Alcohol + Stable Salt --> Nothing

 

[Mohammed salik]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s11_qp_12.pdf


People please help me ..

Q8
Q22
Q29
Q30
Q38

Q30:-(A) Because NaOH will Hydrolyze Ethanenitrile and would produce a salt of Ethanoic acid. (Not ethanoic Acid)

 

[Haya Ahmed]

Alcohol + Stable Salt --> Nothing

so in Nucleophilic addition only nonmetal-CL can be used not metals /???

 

[Haya Ahmed]

Alcohol + Stable Salt --> Nothing

Can you write an equation with "C" Please :3

 

[Haya Ahmed]

Q29:- (D) Because Cold one Breaks double Bond and Forms Diol (two OH groups added ) giving two chiral centers. And with Hot KMnO4 it disrupts the double bind completely which causes this compound to lose one chiral center!

What happened by hot KMnO4 exactly ?

 

[AbbbbY]

Do you have anything like that but for physics?

As a matter of fact, I do.
Gimme a day. I'll gather up all the individual facesheets, merge them and upload them and send you the link.
Or, if you want specific topics, let me know and I'll send you those.

 

[Mohammed salik]

Can you write an equation with "C" Please :3

Equation for Q22 C
Propan-2-0l + SOCl2 gives 2-chloropropane + SO2 +HCL

 

[AbbbbY]

What happened by hot KMnO4 exactly ?

Cleavage occurs and the double bond is split.

If the side being split is CH2, it forms CO2+H2O. If it's CHR then it forms COOH. If it's CRR' then it forms a Ketone. Get it?

 

[Mohammed salik]

What happened by hot KMnO4 exactly ?

Hot one Produces Ketone and/or Carboxillic acid!

 

[Haya Ahmed]

w

Equation for Q22 C
Propan-2-0l + SOCl2 gives 2-chloropropane + SO2 +HCL

hat do you mean by the best yield ?

 

[Mohammed salik]

w

hat do you mean by the best yield ?

Best yeild mean produces Only 2-chloropropane, No other Chloropropanes.
A. will give you both monochloro propanes and a bunch of di- and trichloro as well.
B. will give NO REACTION
C. is correct, the desired compound is the sole product.
D. would give more 2-propanol than 2-chloropropane. (if anything)

 

[Mohammed salik]

The double Bond Come Onn...

Ohhh really ? .. come on ! I mean which part of the diagram ?!

 

[Haya Ahmed]

Cleavage occurs and the double bond is split.

If the side being split is CH2, it forms CO2+H2O. If it's CHR then it forms COOH. If it's CRR' then it forms a Ketone. Get it?

Yeah thanks alot ! .. btw Is it true that the first 5 alkanes are gases !? because It is the first time for me to hear that !

 

[Mohammed salik]

ACtually first 4 are gasses
Under standard conditions, from CH4 to C4H10 alkanes are gaseous; from C5H12 to C17H36 they are liquids; and after C18H38 they are solids

Yeah thanks alot ! .. btw Is it true that the first 5 alkanes are gases !? because It is the first time for me to hear that !

 

[kitkat <3 :P]

But thn it will be cis trans :/

No the structural one is Actually:
CH(Br)=CH(Br)

i

 

[AbbbbY]

ACtually first 10 are gasses
Under standard conditions, from CH4 to C4H10 alkanes are gaseous; from C5H12 to C17H36 they are liquids; and after C18H38 they are solids

You do realize that CH4 -> C4H10 = first 4, right?

Besides, there's no way in hell the first 10 can be gases. Gasoline = octane = most definitely liquid!