Hi, I was confused about this question:" Which of the following is a metalloid?" It gave O, S, Se, Te, and Po options. I am confused. Aren't Polonium and Tellurium both metalloids? I submitted it, and it said Te was the correct answer. Is it because Po is radioactive?

In the periodic table make a staircase starting from left side of B .Now we think that all metals close to staircase are metalloid. But its not true .Al is next to staircase on the metal side and is very metallic. Elements on the top left side are metals and elements on the top right side are more non metals. Even as you go more down on the staircase they become more metals. So true metalloids which have both metallic and non metallic character are in the center of the staircase like As ,Ge ,Sb and Te .These four are more metalloid as compare to other elements.

oh, ok, that makes much more sense now; thank you!