Doubt from reaction mechanism

What is 1,2 H- Shift and how to decide 1,2 H-shift will occur and it occurs only in compounds which exhibit carbocation?

It is process of rearrangement of C+ , it happen whenever a more stable C+ can be formed if the + of C+ is moved to adjacent C with the help of shifting of Hydride ( H)
There are more should shifts like alkyl shift and phenyl shift

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Yes it occurs in carbonation and can be done when carbonation is aquring more stable position not for free radical

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The mechanism we study for dehydration of alcohols to form alkene in ncert class 12 alcohols chapter is E1 or E2 ?

That’s E1

So when E2 occurs in dehydration of alcohols to alkene

See, in dehydration of alcohol, c+ is formed ( and rearranged) and then elimination happens and hence dehydration of alcohol is always e1

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So what is this

Is it given name wrong is its E1 ? in this book

Please clear my doubt of post 8

It is 1degree alcohol and hence C+ won’t be stable here , so C+ is not formed rather simultaneously H escapes and hence E2 is observed.
But even if 2 degree C+ is formed we do E1 , so it is correct that e2 can happen but mostly it is e1 until very bad c+ is being formed

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So can you show in short difference of E1 and E2 for alkenes from alcohol

Basically, in E1 reaction carbocation is formed, whereas in E2 reaction no carbocation of formed

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@abhijit_2020 in E1 reaction C+ is formed and hence there is a chance of rearrangement of C+ and formation of totally different product whereas in E2 reaction C+ is not formed , there is simultaneous removal of H and OH2+

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