Question

Molecularity of reaction cannot be zero ?

Answer 1

Yes, it's right molecularity of a reaction can't be zero because as we know molecularity is defined as a no. of particles or reactants of a specific reaction which comes in contact to make a desired product..
So, it is not possible to make a product or complete a reaction without reaction between reactants of specific reaction or not possible a zero order reaction...

Answer 2

If it is 0, then it means that reaction has not occur.
So,to react 2 or more products, molecularity is must.