A sintered alumina ceramic has $\rho_exp = 3.75$ g/cm³. Theoretical $\rho_th = 3.98$ g/cm³ (α-Al₂O₃). Find porosity. $$ P = \left(1 - \frac3.753.98\right) \times 100% = (1 - 0.9422) \times 100% \approx 5.78% $$
A is a characteristic of matter that can be observed or measured without changing the substance's identity. For solid objects, engineers primarily focus on: Volume ( 5.4 calculating properties of solids
For elemental solids: $$ \textAPF = \fracn \cdot \frac43 \pi r^3a^3 $$ Where $r$ is the atomic radius. For common structures: A sintered alumina ceramic has $\rho_exp = 3