Question

18. When is an atom unlikely to react and form chemical bonds?

Answer 1

An atom is unlikely to react when it is stable. That is when it's shell is complete. Due to the completion of the shell, no other electron can combine through any form of bonding. Hope i helped.

Answer 2

If the atom is in the far right column of the period table as they are unreactive elements, and also when all the electrons are filled within the element.

I hope this helps you! :)