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Question

Which of the statements are correct about above reaction?
(i) (a) and (e) both are nucleophiles.
(ii) In (c) carbon atom is sp3 hybridised.
(iii) In (c) carbon atom is sp2 hybridised.
(iv) (a) and (e) both are electrophiles.
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Solution
(i) (a) and (e) both are nucleophiles.
(iii) In (c) carbon atom is sp2 hybridised.
Explanation:
HO− and Cl− are nucleophiles.
In (iii), C atom is sp2 hybridised due to formation of \[\ce{C - OH}\] bond and breaking of \[\ce{C - Cl}\] bond simultaneously. So, in the transition state, the C atom is bonded to only 3 H atoms completely.
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Nucleophilic Substitution: Influences of solvent polarity: The reaction rate (SN2) of 2-bromopropane and NaOH in ethanol containing 40% water is twice slower than in absolute ethanol. Hence the level of solvent polarity has an influence on both SN1 and SN2 reactions but with different results. Generally speaking, a weak polar solvent is favourable for SN2 reaction, while a strong polar solvent is favourable for SN1. Generally speaking, the substitution reaction of tertiary haloalkane is based on SN1 mechanism in solvents with a strong polarity (for example ethanol containing water). |
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OR
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