What are the shared properties of metals and metalloids

both are shiny and are solid at room temperatures

some are not shiny so this answer will mislead you a little but all nonmetals on metal are solid in room temperature

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.