Final answer:
One atom of a Group 2 element will react with two atoms of a Group 17 element to form a stable, neutral bond as Group 2 elements need to lose two electrons and Group 17 elements need to gain one electron.
Step-by-step explanation:
The question asks how many atoms of a Group 17 element would be needed to react with one atom of a Group 2 element to form a neutral bond. To answer this, we need to understand electron configurations and how elements achieve stable electron arrangements.
Elements of Group 2 have two electrons in their outer shell and need to lose both to achieve the stable electron configuration of the nearest noble gas. On the other hand, elements of Group 17, known as the halogens, have seven electrons in their outer shell and need to gain one electron to complete their octet.
According to the Lewis electron structures, a Group 2 element will form two bonds, as it has two electrons to lose, while a Group 17 element will form only one bond, as it only needs to gain one electron. This means one atom of a Group 2 element will react with two atoms of a Group 17 element to form a stable, neutral compound.