Determine the number of atoms per unit cell for each metal.
(a) Polonium

A unit cell is the smallest repeating unit in a crystal lattice that reflects the symmetry and structure of the entire crystal. It defines the arrangement of atoms in a solid and is characterized by its dimensions and angles. Understanding the unit cell is crucial for determining the number of atoms it contains, which can vary based on the type of crystal structure.

The Atomic Packing Factor (APF) is a measure of how efficiently atoms are packed in a unit cell. It is calculated as the volume occupied by the atoms in the unit cell divided by the total volume of the unit cell. Different metals have different APFs depending on their crystal structures, which influences their physical properties and the number of atoms per unit cell.

Crystal structure refers to the ordered arrangement of atoms in a crystalline material. Metals can adopt various crystal structures, such as face-centered cubic (FCC), body-centered cubic (BCC), or hexagonal close-packed (HCP). The specific structure of a metal like polonium will determine how many atoms are present in its unit cell, which is essential for understanding its properties and behavior.