Question

Which of the following pairs represent electrophiles?
(a) AlCl₃, H₂O
(b) SO₃, $NO_2^+$
(c) BF₃, H₂O
(d) NH₃, SO₃

Answer 1

Explanation:

option a is correct

AlCl3, H20

Answer 2

Answer:

(b) SO₃, NO₂⁺ is the correct answer. Both of them are electrophiles.

Explanation:

What are electrophiles:

• Electrophiles are species that are electron-deficient but attracted to an electron-rich centre.
• Electrophiles accept an electron pair in order to establish a connection with a nucleophile that includes proton and base interactions.

AlCl₃, H₂O, BF₃, NH₃ and SO₃:

• AlCl₃ is an electrophile because after bonding also Al is having only 6 electron in its octet instead of 8 so it is an electron deficient species.

• H₂O is a nucleophile.
• BF₃ is an electrophile.
• NH₃ consists of Nitrogen which does not have D orbital. On the other hand it has a lone pair of electron which repels when other electron approach towards it.  As a result NH₃ can never act as an electrophile. This is because there is repulsion between the lone pair of electron and other approaching electrons.
• SO₃ is an electrophile.