Question

Which resonance contributor in each pair makes the greater contribution to the resonance hybrid?

Short answer

Here we have to find which resonance contributor in each pair makes the greater contribution to the resonance hybrid:

a)

b)

c)

d)

Step-by-step solution

What is resonance contributors

Resonance contributors involve the 'imaginary movement' of pi-bonded electrons or of lone-pair electrons that are adjacent to pi bonds. You can never shift the location of electrons in sigma bonds – if you show a sigma bond forming or breaking, you are showing a chemical reaction taking place.

Final answer

d)