The electron flow arrow always starts from the nucleophilic center to the electrophilic Centre.
What is nucleophilic ?
The term "nucleophile" refers to an atom or molecule that searches for a positive centre during a chemical reaction, such as the nucleus of an atom, since the nucleophile has an accessible electron pair for bonding.
What is electrophilic ?
An atom or molecule that searches for an atom or molecule that has a pair of free electrons during a chemical process. Lewis acids, which absorb electron pairs, are electrophilic chemicals; many of them are also Brnsted acids (compounds that donate protons).
The electron flow arrow always starts from the nucleophilic center to the electrophilic Centre. The arrow starts from the electrons.
Mechanism with arrows:-
Therefore, The electron flow arrow always starts from the nucleophilic center to the electrophilic Centre.
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