To determine what substance the unknown sample is made of, we need to calculate its density and then compare it to the densities of the substances in the given table.
1. Calculate the density of the unknown sample:
The mass of the unknown sample is given as [tex]\(9.5\)[/tex] grams, and its volume is [tex]\(2.1\)[/tex] cubic centimeters. The density [tex]\(\rho\)[/tex] is calculated using the formula:
[tex]\[
\rho = \frac{\text{mass}}{\text{volume}}
\][/tex]
Plugging in the given values:
[tex]\[
\rho = \frac{9.5 \, \text{g}}{2.1 \, \text{cm}^3} \approx 4.523809523809524 \, \text{g/cm}^3
\][/tex]
2. Compare the calculated density with the densities of the known substances:
According to the table:
- Aluminum has a density of [tex]\(2.7 \, \text{g/cm}^3\)[/tex]
- Copper has a density of [tex]\(9.0 \, \text{g/cm}^3\)[/tex]
- Iron has a density of [tex]\(7.9 \, \text{g/cm}^3\)[/tex]
- Titanium has a density of [tex]\(4.8 \, \text{g/cm}^3\)[/tex]
3. Identify the closest match:
The calculated density of the unknown sample is approximately [tex]\(4.523809523809524 \, \text{g/cm}^3\)[/tex]. Comparing this with the densities of the known substances, it is clear that the calculated density is closest to the density of titanium, which has a density of [tex]\(4.8 \, \text{g/cm}^3\)[/tex].
Therefore, the unknown sample is most likely made of titanium.
The correct answer is:
D. titanium
