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What is the difference between electrophilic addition and nucleophilic substitution in terms of drawing the mechanism etc.
Original post by Username123455
What is the difference between electrophilic addition and nucleophilic substitution in terms of drawing the mechanism etc.

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Reply 2
Original post by Username123455
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idk how helpful this is but here u go
Electrophilic addition

Involves an alkene

Arrow from double bond

Arrow to the carbocation


Nucleophillic substitution

Involves a haloalkane

Arrow from nucleophile to carbon involved in a carbon-halogen bond

Arrow from the carbon halogen bond to the halogen

If ammonia is the nucleophile the a N-H bond must be broken the arrow goes towards the positive N

Original post by Hellllpppp
Electrophilic addition

Involves an alkene

Arrow from double bond

Arrow to the carbocation


Nucleophillic substitution

Involves a haloalkane

Arrow from nucleophile to carbon involved in a carbon-halogen bond

Arrow from the carbon halogen bond to the halogen

If ammonia is the nucleophile the a N-H bond must be broken the arrow goes towards the positive N


Thank you!
Reply 5
Original post by Hellllpppp
Electrophilic addition

Involves an alkene

Arrow from double bond

Arrow to the carbocation


Nucleophillic substitution

Involves a haloalkane

Arrow from nucleophile to carbon involved in a carbon-halogen bond

Arrow from the carbon halogen bond to the halogen

If ammonia is the nucleophile the a N-H bond must be broken the arrow goes towards the positive N


With the partial charges for nucleophilic substitution, is the carbon more electronegative than the halogen?
Original post by Jaz._bg
With the partial charges for nucleophilic substitution, is the carbon more electronegative than the halogen?

The halogen is more electronegative so has a partial negative charge. The carbon has a partial positive charge so attracts the nucleophile.
Reply 7
Original post by Hellllpppp
The halogen is more electronegative so has a partial negative charge. The carbon has a partial positive charge so attracts the nucleophile.

Thank you very much I have my chemistry mock tomorrow I'm so scared :frown:
Original post by Jaz._bg
Thank you very much I have my chemistry mock tomorrow I'm so scared :frown:

Good luck I’m sure you’ll be fine, make sure you’re well rested. Its never productive to do a all-nighter before an exam.
Original post by Jaz._bg
Thank you very much I have my chemistry mock tomorrow I'm so scared :frown:

Good luck, hope it went well!
Original post by Username123455
What is the difference between electrophilic addition and nucleophilic substitution in terms of drawing the mechanism etc.


I love that i found this i have literally been revising it today for my mock next week.

nucleophilic substitution is when you have NH3, OH or CN replacing a halogen in a haloalkane. The curly arrows go from the nucleophile to the carbon the funtional group is on. then from that bond onto the halogen. final product is an alkane with the nucleophilic species plus the halogen which now has a lone pair and a negative charge.

electorphilic addition is only for an alkene. the curly arrow goes from the bond between the electrophilic species to the double bond. Next step has the carbons now having a single bond and one having 2 hydrogens and the first element of the electrophilic species. The second carbon had two hydrogens and then a space with a positive charge. The remaining element of the species has a negative charge. The curly arrow goes from the negative species to the carbon. Final product is an alkane of some sort and nothing else.
Original post by Hellllpppp
Good luck I’m sure you’ll be fine, make sure you’re well rested. Its never productive to do a all-nighter before an exam.


Original post by Username123455
Good luck, hope it went well!

Thank you both so much it was super difficult so I can't say I'm expecting much but electrophilic addition came up and I can definitely say that that question went well thanks to this thread! :biggrin:
Original post by Jaz._bg
Thank you both so much it was super difficult so I can't say I'm expecting much but electrophilic addition came up and I can definitely say that that question went well thanks to this thread! :biggrin:

I’m glad this helped - I hope you get the results you need :biggrin:
Original post by Jaz._bg
Thank you both so much it was super difficult so I can't say I'm expecting much but electrophilic addition came up and I can definitely say that that question went well thanks to this thread! :biggrin:

Aw hope you done well, I'm having my chem mock soon too! Have any tips for doing well:h:
Original post by terrafir
the curly arrow goes from the bond between the electrophilic species to the double bond.

I hope your mock next week goes well :biggrin: Just be careful with the directions of your arrows. They show the movement of electrons so it must go from the double bond. Not sure if you forgot to mention it but there is also an arrow from the bond in what you’ve called the “electrophilic species” to the “remaining element of the electrophilic species” which is why it has the negative charge you’ve recognised.
Original post by Username123455
Aw hope you done well, I'm having my chem mock soon too! Have any tips for doing well:h:

Good luck you'll do amazing!!! I did a lot of past paper questions and that helped me in the exam because I saw some questions that I recognised from doing previous exam questions so that's probably best. Flashcards for definitions and calculations for sure if you haven't made your own there should be lots on Quizlet that are helpful! If you want to revise the content like make notes spider diagrams always help me condense my notes down to the important parts that you need for the questions :h:

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