Ferrous oxide has a cubic structure and each dege of the unit cell is 5.0 Å. Assuming density of the oxide as `"4.0 g cm"^(-3)` then the number of `Fe^(2+)` and `O^(2-)` ions present in each unit cell will be

Options

A. Four `Fe^(2+)` and four `O^(2–)`
B. Two `Fe^(2+)` and four `O^(2–)`
C. Four `Fe^(2+)` and two `O^(2–)`
D. Three `Fe^(2+)` and three `O^(2–)`

Answer

A