Electrophili addition = heterolytic fission Watch

Ari Ben Canaan
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Just a small confirmation I require here.

In the electrophilic addition of H-Br to an alkene there is a movement of electrons from the Hydrgoen (in H-Br) to the Bromine.

This would be considered heterolytic fission, correct ?

Also, there are two dative bonds formed in the addition of H-Br.

C-->H and C<---Br correct ?


EDIT : One other thing.

The lone pairs in the cyanide ion are on the CARBON and so is the negative charge, correct ?
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EierVonSatan
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(Original post by Ari Ben Canaan)
Just a small confirmation I require here.

In the electrophilic addition of H-Br to an alkene there is a movement of electrons from the Hydrgoen (in H-Br) to the Bromine.

This would be considered heterolytic fission, correct ?
Yes.

Also, there are two dative bonds formed in the addition of H-Br.

C-->H and C<---Br correct ?
No, not really.

EDIT : One other thing.

The lone pairs in the cyanide ion are on the CARBON and so is the negative charge, correct ?
There are two sets of lone pairs - one on each atom, but the formal charge resides on the carbon :yes:
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ilovedubstep
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It is heterolytic fission correct. And you're right about the dative bonds as well. Not sure where you got the cyanide ion from though.
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Ari Ben Canaan
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(Original post by EierVonSatan)
Yes.



No, not really.



There are two sets of lone pairs - one on each atom, but the formal charge resides on the carbon :yes:
I'm pretty sure there are some dative bonds formed formed somewhere in the mechanism.

(Original post by ilovedubstep)
It is heterolytic fission correct. And you're right about the dative bonds as well. Not sure where you got the cyanide ion from though.
Two conflicting answers here.
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ilovedubstep
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(Original post by EierVonSatan)
No, not really.
The H Br splits into H+(0 Electrons) and Br-(8 Electrons). So when the hydrogen bonds with the carbon it must be a dative bond. Likewise with the bromide ion.
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EierVonSatan
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(Original post by ilovedubstep)
The H Br splits into H+(0 Electrons) and Br-(8 Electrons). So when the hydrogen bonds with the carbon it must be a dative bond. Likewise with the bromide ion.
I suppose so, but just about every bond formed in organic chemistry will be a 'dative bond' - but nobody draws it as such. The distinction is pointless :dontknow:
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ilovedubstep
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(Original post by EierVonSatan)
I suppose so, but just about every bond formed in organic chemistry will be a 'dative bond' - but nobody draws it as such. The distinction is pointless :dontknow:
He didn't say whether to draw it as such, he asked whether they were dative bonds. Which they are.
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EierVonSatan
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(Original post by ilovedubstep)
He didn't say whether to draw it as such, he asked whether they were dative bonds. Which they are.
Fine. I'll not bother in future
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Ari Ben Canaan
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I sense a slightly tense atmosphere. Anyways, gentleman, thank you both for your points of view.

I've taken all of them into account. Much obliged !
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taunt
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(Original post by EierVonSatan)
I suppose so, but just about every bond formed in organic chemistry will be a 'dative bond' - but nobody draws it as such. The distinction is pointless :dontknow:


is cholrine and ethene reaction a heterolytic bond fission???
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EierVonSatan
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(Original post by taunt)
is cholrine and ethene reaction a heterolytic bond fission???
The Cl-Cl bond is broken heterolytically yes.
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taunt
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(Original post by EierVonSatan)
The Cl-Cl bond is broken heterolytically yes.


eh?


I thought because they are same atom, so its homolytic, I dont understand why they are heterolytic lol
Im bordeerline suicidal lol, I cant seem to get anything lol
and iv got my exam on friday.......
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EierVonSatan
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(Original post by taunt)
eh?


I thought because they are same atom, so its homolytic, I dont understand why they are heterolytic lol
Im bordeerline suicidal lol, I cant seem to get anything lol
and iv got my exam on friday.......
Homo = same
Hetero = different

Cl2 is a homonuclear diatomic = A molecule made of two atoms, where both atoms are the same element.

But the bond can be split either evenly or unevenly regarding where the electrons go. When Cl2 reacts with ethene, the double bond induces a polarisation in the Cl-CL bond...then the electrons move from the bond to one of the chlorines (pushed by the electrons from ethene). So one chlorine ends up with both electrons from the bond and the other with no electrons. This is heterolytic fission as the two atoms have different numbers of electrons after the bond is broken. Clearer?
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taunt
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(Original post by EierVonSatan)
Homo = same
Hetero = different

Cl2 is a homonuclear diatomic = A molecule made of two atoms, where both atoms are the same element.

But the bond can be split either evenly or unevenly regarding where the electrons go. When Cl2 reacts with ethene, the double bond induces a polarisation in the Cl-CL bond...then the electrons move from the bond to one of the chlorines (pushed by the electrons from ethene). So one chlorine ends up with both electrons from the bond and the other with no electrons. This is heterolytic fission as the two atoms have different numbers of electrons after the bond is broken. Clearer?

yep



Thankyou......................
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illusionz
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(Original post by EierVonSatan)
Homo = same
highest occupied molecular orbital :P



Yes, I'm being annoying
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