What is a nucleophile? [ENDORSED]

[Mary Becerra 2D]

What exactly is a nucleophile? Also, can there be more than one nucleophile with molecule interactions?

[Kelly Seto 2J]

A nucleophile is a chemical species that is attracted to positively charged particles; it's also in a sense the same as a Lewis base in that it acts as an "electron donor" to form bonds. I'm not sure about the second half of your question though

[Mika Sonnleitner 1A]

A nucleophile is any electron rich species that donates electrons to elecrophiles to form a chemical bond in a reaction. In substitution reactions, for example, nucleophiles can be electrostatically attracted to a positive central atom, and therefore donate electrons to bond with that central atom. This could also cause another bonded element/compound to leave, called the leaving group.

[Esin Gumustekin 2J]

Does this mean that a nucleophile is always negatively charged?

[Xihui Yin 1I]

Not necessarily. What matters is that that have a pair of electrons that can be used to form a bond with an electron-deficient species. This means they either have lone pairs (H2O, NH3, OH-), a pi bond (ethene) or a partial negative charge.

[K Stefanescu 2I]

I believe Dr. Lavelle mentioned this helpful way to remember the definition in class: a nucleophile likes the (positively charged) nucleus.
(This is clearly shorthand and does not go into details regarding the charge of the nucleophile, as mentioned in other posts, but can be useful in case you forget on an exam.)

[Chem_Mod]

A nucleophile is an electron rich species that can be neutral or negatively charged.
For example H₂O and ^-OH are both nucleophiles due to the available lone pairs on the oxygen atom.

[705748759]

I like to think of it as nucleophiles like the (positively charged) nucleus.