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Q.
In which of the following reactions, only single isomer of alkene is formed?
Hydrocarbons
Solution:
It has only one type of $\beta-H$ and product alkene does not has stereoisomers. $(b)$ form pair of geometrical isomers. $(c)$ does not form alkene in the given condition. $(d)$ has more than one types of $\beta-H$, form more than one products.