Question

what is the reasonable or mesomeric effect ? Describe the types along with example of each type​

Answer 1

AnSwer :-

we have seen that resonance or mesomerism involves the movement or flow of electrons in conjugated system (having σ and π) bonds in alternative positions).

$\Large\star$This leads to centres of low and high electron densities resulting in positive and negative charges respectively.

The phenomenon is termed as resonance effect (R-effect) or Mesoameric effect (M-effect).

It has two types :-

(i) +R or +M effect :- A group is said to haven+R or +M effect when the displacement of the electron pair is away from it.

For example :-

$\sf - O- H, \: -O-R, \: NH_2, \: -N \: HR, \: -S-R,$

(ii) -R or -M effect :- A group is said to have -R or -M effect when the displacement of the electron pair is towards it.

For example :-

$\sf -NO_2 \: </p><p>, >C = O, \: -CHO, \: -COOR, \: -CN \: etc..$

Answer 2

Answer:

AnSwer :-

we have seen that resonance or mesomerism involves the movement or flow of electrons in conjugated system (having σ and π) bonds in alternative positions).

\Large\star⋆ This leads to centres of low and high electron densities resulting in positive and negative charges respectively.

The phenomenon is termed as resonance effect (R-effect) or Mesoameric effect (M-effect).

It has two types :-

(i) +R or +M effect

(ii) -R or -M effect :-