Question

1. iron has a density of 7.86 g/cm³. a sample of an unknown metal is measured and found to be 2.25 cm x 1.5 cm x 2.25 cm. the mass of the sample is 55.75 g. is the sample iron? explain.

Explanation:

Step1: Calculate volume of unknown metal

$V = 2.25\times1.5\times2.25$
$V=7.59375\ cm^{3}$

Step2: Calculate density of unknown metal

$
ho=\frac{m}{V}=\frac{55.75}{7.59375}$
$
ho = 7.34\ g/cm^{3}$

Step3: Compare densities

The density of iron is $7.86\ g/cm^{3}$, and the density of the unknown - metal sample is $7.34\ g/cm^{3}$. Since $7.34
eq7.86$, the sample is not iron.

Answer:

No, the sample is not iron because the density of the sample ($7.34\ g/cm^{3}$) is different from the density of iron ($7.86\ g/cm^{3}$).