Question

Helium, He, is a nonmetallic gas and the second element in the periodic table. Rather than being placed adjacent to hydrogen, H, however, helium is placed on the far right of the table because
A) hydrogen and helium repel one another.
B) the sizes of their atoms are vastly different.
C) they come from different sources.
D) helium is most similar to other group 18 elements.

Answer

This answer is hidden. It contains 1 characters.