The zincblende structure of ZnS has the relatively large sulfide ions arranged at the lattice points of a face-centered cubic structure. The edge length of this cubic unit cell is 540.9 pm. Determine the density of zincblende. A) 0.244 g/cm³ B) 1.02 g/cm³ C) 2.05 g/cm³ D) 4.09 g/cm³ E) 8.18 g/cm³

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Quizplus · Accepted Answer

The density of zincblende can be calculated using the formula $\rho = \frac{Z \times M}{a^3 \times N_A}$, where $\rho$ is the density, $Z$ is the number of formula units per unit cell (which is 4 for zincblende), $M$ is the molar mass of ZnS (approximately 97.46 g/mol), $a$ is the edge length of the cubic unit cell converted to cm (540.9 pm = 5.409 x 10^-8 cm), and $N_A$ is Avogadro's number (6.022 x 10^23 mol^-1). Plugging in the values, the calculation yields a density close to 4.09 g/cm^3, making option D correct.

The Zincblende Structure of ZnS Has the Relatively Large Sulfide