What are properties of the group of elements on the periodic table that have seven valence electrons? (2 points) High reactivity, metallic
High reactivity, nonmetallic
Low reactivity, metallic
Low reactivity, nonmetallic

Which of the following did jj thompson discover about atoms? a)an atom has an internal structure. b) atoms are tiny indivisible particles. c)electrons orbit the nucleus of an atom. d) the nucleus of an atom contains protons and neutrons.