Question

Choose the nonmetallic elements from the list. Check all that apply. yttrium oxygen boron polonium argon gallium carbon

Answer 1

Oxygen and Carbon are non metallic elements as a there is no reversal of polarity in the nucleus. If you have a valid atomic model these things become apparent.

Answer 2

Oxygen and Carbon are non metallic elements as there is no reverse of polarity in there nucleus. The affection of an element to accept electrons to form an positive ion is called its non-metallic or electronegative character.  Non metallic character always increase across a period while metallic character decrease.