Write the resonance structures for SO3, NO2 and

The single Lewis structure based on the presence of two single bonds and one double bond is not enough to represent the molecule precisely as it presents unequal bonds. Hence, the concept of resonance was introduced to deal with this difficulty.


a) There are three possible resonance structures for SO3 which are given below:



The structure I, II and III represent the three canonical forms (resonating structures) of SO3.


The structure IV represents the structure of SO3 more accurately. This is also called resonance hybrid.


b) There are two possible resonance structures for SO3 which are given below:



The structure I and II represent the two canonical forms (resonating structures) of NO2


The structure III represents the structure of NO2 more accurately. This is also called resonance hybrid.


c) There are three possible resonance structures for NO3- which are given below:



The structure I,II and III represent the three canonical forms (resonating structures) of NO3-


The structure IV represents the structure of NO3- more accurately. This is also called resonance hybrid.


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