The diagram illustrates the arrangement of atoms in a specific crystal. Each atom is positioned at a corner of a cube. The mass of each atom is $3.5 \times 10^{-25}\,\text{kg}$. The density of the crystal is $9.2 \times 10^3\,\text{kg m}^{-3}$. What is the smallest separation between the centres of two neighbouring atoms?
- A$3.8 \times 10^{-29}\,\text{m}$
- B$6.2 \times 10^{-15}\,\text{m}$
- C$3.4 \times 10^{-10}\,\text{m}$
- D$3.0 \times 10^{-9}\,\text{m}$