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प्रश्न
Alkenes 
and carbonyl compounds 
, both contain a π bond but alkenes show electrophilic addition reactions whereas carbonyl compounds show nucleophilic addition reactions. Explain.
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उत्तर
Carbonyl group is polar in nature. Due to larger electronegativity of oxygen as compared to carbon, carbon acquires partial positive charge while O acquires partial negative charge.
Because of slight positive charge on C atom, it is attacked by nucleophiles and, therefore, undergoes nucleophilic addition reaction.
Ethylenic double bond is a non-polar bond and is a source of electrons. Therefore, it is attacked by electrophiles and undergoes electrophilic addition reactions.
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\ce{(CH3)3C-C-CH3}\\
\phantom{....}||\\
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||\\
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\end{array}\]
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OR
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| (i) |  |
| (ii) |  |
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||\phantom{.........}\\
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