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Nucleophilic substitution - Need help

how many different alkenes can be formed when 2-bromo-2 methylbutane reacts with ethanolic potassium hydroxide?
why is the answer 2 I can see it forming 3 one from the top methyl group.
Reply 1
Original post by abdullah9999
how many different alkenes can be formed when 2-bromo-2 methylbutane reacts with ethanolic potassium hydroxide?
why is the answer 2 I can see it forming 3 one from the top methyl group.


draw the displayed formula for 2-bromo-2-methylbutane: there are two adjacent end carbon atoms to the carbon atom with bromine attached to it.

one of the hyddrogens in these would get removed.

so there's only two. :smile:

cheers
Untitled.png

Thank you for the reply, I can still see 3, I'm probably drawing it wrong I don't know.
Original post by abdullah9999
Untitled.png

Thank you for the reply, I can still see 3, I'm probably drawing it wrong I don't know.


Hey, basically 1 and 2 will produce the same isomers. Because both methyl groups (1 and 2) can rotate to switch places so they are in fact the same.
Omg, thank you so much I've been sat here for the last 30 mins trying to figure this one out now it all makes sense. Thanks :biggrin:
Original post by abdullah9999
Omg, thank you so much I've been sat here for the last 30 mins trying to figure this one out now it all makes sense. Thanks :biggrin:


Haha no you're welcome, any other Qs?
I revise better when doing random qs like this one.
I usually have a lot ill keep going and one should come up. ty :smile:
These questions I have had for quite a while:
write both ionic and and full stiochiometric equations of when:

Calcium carbonate dissolves in dilute hydrochloric acid with the evolution of a colourless gas

Ammonia gas dissolves in dilute nitric acid
Reply 8
Original post by abdullah1443
Untitled.png

Thank you for the reply, I can still see 3, I'm probably drawing it wrong I don't know.

You've drawn it wrong, the methyl group shouldn't be on carbon atom number 2 like the Br is. It should be on carbon atom number 3.
Reply 9
Original post by AAero
You've drawn it wrong, the methyl group shouldn't be on carbon atom number 2 like the Br is. It should be on carbon atom number 3.

They have drawn it correctly, you're talking about 2-bromo-3-methylbutane:

They were to draw 2-bromo-2-methylbutane:

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