Answer:
Step-by-step explanation:
A. Metals are shiny, usually solid at room temperature, malleable, ductile, and highly conductive. In contrast, ionic compounds are brittle. Molecular compounds are often gases at room temperature.
b. Metals have very few valence electrons. Their outermost p-orbitals are empty. This allows their electrons (including those from their d-orbitals) to move freely between metal atoms. The movement of electrons is electricity, so this mobile "sea of electrons" is what causes metals' conductivity.