A metallic object holds a charge of -3.8 ´ 10-6 C. What total number of electrons does this represent? (e = 1.6 ´ 10-19 C is the magnitude of the electronic charge.)

Ahypothetical metal has an orthorhombic unit cell for which the a, b, and c lattice parameters are 0.413 nm, 0.665 nm, and 0.876 nm, respectively. (a) if there are 8 atoms per unit cell and the atomic packing factor is 0.536, determine the atomic radius (in nm). (b) if the density is 3.99 g/cm3, calculate the metal's atomic weight (in g/mol).