Question: how many atoms of ca are present in each unit cell?
Answer: A face-centered Ca unit cell has one-eighth of an atom at each of the eight corners (8×18=1 8 × 1 8 = 1 atom) and one-half of an atom on each of the six faces 6×12=3 6 × 1 2 = 3 ), for a total of four atoms in the unit cell.