Electrophiles and Nucleophiles

Electrophiles

ElectroPhile
Electro = Electron
Phile = Loving or Seeking
So, electrophile means electron loving or electron seeking which means it is an electron deficient species (i.e., Lewis acid).

A species which can accept a pair of electrons is called an electrophilic reagent or elelctrophile. Electrophile seeks an electron-rich (negatively charged) site in a molecule for attack. It may be positively charged ion or electron-deficient molecule (molecule having an atom with sextet). Common electrophiles are:
Positively charged ions: H⁺, H₃O⁺, X⁺, NO₂⁺, NO⁺, HSO₃⁺, C₆HN₂⁺, R₃C⁺, etc.
Electron-deficient molecules: BF₃, AlX₃, SO₃, CO₂, ICl, SnCl₂, FeCl₃, etc.

Nucleophiles

NucleoPhile
Nucleo = Nucleus (Positive Cherged)
Phile = Loving or Seeking
So, nucleophile means nucleus loving or positive charged species seeking which means it is an electron sufficient species (i.e., Lewis base).

A species which can donate an unshared electron pair is called a nucleophilic reagent or nucleophile. Nucleophile seeks an electron-deficient site for the attack. It may be a negatively charged ion or a molecule having an unshared electron pair. Some common nucleophiles are:
Negatively charged ion: H^–, HO^–, CN^–, RO^–, RS^–, RC≡C^–, RCOO^–, NH₂^–, CH(COOR)₂^–, etc.
Electron-rich molecules: H₂O, ROH, RNH₂, NH₃, RN, RMgBr, RLi, etc.

Which of the following statement is incorrect about electrophiles?

A. Electrophiles are positively charged or neutral species having vacant orbitals
B. The electrophiles are attacked by the most electron-populated part of one nucleophile
C. Chemical species that do not satisfy the octet rule such as carbenes and radicals are electrophiles
D. Electrophiles are Lewis base

Which of the following is not true about nucleophile?

A. Donates an electron pair to an electrophile to form a chemical bond
B. All molecules or ions with a free pair of electrons or at least one pi bond can act as nucleophiles
C. Nucleophile are Lewis acids by definition
D. A nucleophile becomes attracted to a full or partial positive charge

Which of the following statements is true about ammonia and water?

A. Ammonia is more basic and more nucleophilic than water
B. Ammonia is less basic and less nucleophilic than water
C. Ammonia is more basic but less nucleophilic than water
D. Ammonia is less basic but more nucleophilic than water

Answer: 1- D | 2- C | 3 - A