## Chemistry: The Molecular Science (5th Edition)

The volume of the metal is (1.0cm)(2.0cm)(10.0cm) = 20.0cm$^3$. Density is mass divided by volume. The density of the metal is (54.0g)/(20.0cm$^3$) = 2.70 g/cm$^3$ = 2.70 g/mL. According to Table 1.1, Aluminium has a density of 2.70 g/mL. Therefore, the unknown metal must be aluminium. (Any pure substance of a metal will always have the same density, regardless of the size.)