-. Simple Cubic Unit Cell a. Consider one unit cell and assume the length of the side of the cube is "a". Remember that "a" is the distance between the centers of two adjacent atoms. How long is "a", the edge of a unit cell, in terms of radius, r, of an atom? b. A simple cubic cell has the equivalent of only 1 atom. Recall the volume of sphere with radius, 1, is expressed as V = 4/3 Tư. With this information, find the total volume of all the spheres in this unit cell, expressed in terms of r. To do this, take the total number of atoms and multiply it by the volume of one atom, with radius, 1) c. Find the volume of the entire unit cell including the empty space in terms of r. Remember for a cube the volume, V= 1lxw xh. You already know the edge length of the side in terms of “r" based in the earlier questions. d. Find the fraction of the total volume of the cube (which is the unit cell's volume) is occupied by the atoms. Express this as percent and write your answer in the summary table.

1. Large biomolecules can be crystallized into lattices with the same unit cell features as more simple ionic solids. In these cases, a lattice point is occupied by one macromolecule instead of one atom or ion. The crystalline form of a certain protein has density 1.287 g/cm³ and face-centered cubic unit cells with length 12.3 nm. What is the molar mass of the protein?

1. The radius of gold atom is 1.44 Å. What is the length of the unit cell for gold crystals whose atoms are packed according to fcc lattice?

Metallic strontium crystallizes in a face-centered cubic lattice, with one Sr atom per lattice point. If the metallic radius of Sr is 215 pm, what is the volume of the unit cell in pm³ and in cm³ ? 3 pmº cm³