In which case is an atom least likely to bond with other atoms

answer:

Explanation:

When an atom has deficiency or excess of electrons then in order to attain stability the atom will react readily with another atom. Whereas an atom whose outermost electron shell is completely filled is least likely to bond with other atoms as the atom is stable due to completely filled shell.

why do the isotopes of a particular element behave differently in nuclear reactions but the same in chemical reactions? chemical reactions involve changes to electrons in an atom; isotopes do not differ in electrons, and so they react the same way during chemical changes.