Resonance

Question 1

types of conjugation

Answer 1

1. pi-pi conj
2. +, pi conj
3. -, pi conj
4. LPE, pi conj
5. OE, pi conj

Question 2

all atoms participating in conjugation are sp2 hybridised

Answer 2

no element of the 2nd period can make more than 4 bonds

Question 3

most stable

Answer 3

cyclopropyl methyl carbocation

Question 4

aromaticity

Answer 4

cyclic/ planar/ conjugated/ must obey hackel’s rule (4n+2)pi n=0,1,2,3…

Question 5

antiaromatic substance

Answer 5

cyclic/ planar/ conjugated/ must have 4npi. n=1,2,3…

Question 6

non-aromatic substance

Answer 6

must be non-planar

Question 7

order of stability

Answer 7

aromatic> non-aromatic> anti aromatic

Question 8

quasi-aromatic species

Answer 8

they are ionic solid
high melting point
highly polar
high resonance energy
highly stable

Question 9

NOTE

Answer 9

if one ring is aromatic and other is not, it will make it all aromatic

Question 10

azulene

Answer 10

blue coloured ionic solid, higly aromatic, soluble in polar solvent

Question 11

after resonance

Answer 11

double bond aquire single bond charachter and single bond- partial double bond chr,

Question 12

resonance energy

Answer 12

always exo
stability factor
more the RE more stab
RE= PE of most contributing str

Question 13

resonance hybrid is more stable than its RS

Answer 13

A-aromaticity
E-equivalent/ extended resonance
R-resonance
H-hyperconjugation
I-inductive effect

Question 14

electron releasing group will stabilise benzyl carbocation and electron withdrawing group will destabilize the benzylic carbocation