Aluminum (Al) has a density of 2.70 g/cm³ and crystallizes in a face-centered cubic structure. What is the unit cell edge length? A)2.47 $\times$ 10^-³ pm B)40.0 pm C)405 pm D)321 pm E)255 pm

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The density of aluminum (Al) is given as 2.70 g/cm³, and it crystallizes in a face-centered cubic (FCC) structure. In an FCC structure, there are 4 atoms per unit cell. The atomic mass of aluminum is approximately 26.98 g/mol, and Avogadro's number is 6.022 × 10²³ atoms/mol. The formula to calculate the volume of the unit cell (V) based on the density (d), mass of the atoms in the unit cell (m), and Avogadro's number (N_A) is V = m / (d * N_A). Substituting the given values and solving for the edge length (a) of the unit cell (since V = a³ for a cube), we find that the edge length is approximately 405 pm.

Aluminum (Al) Has a Density of 2 ×\times× 10-3 Pm B)40

Aluminum (Al) Has a Density of 2 $\times$ 10^-³ Pm
B)40