Energy bands are considered continuous due to the large number of closely spaced energy levels. The range of energy levels in a crystal of copper is approximately 1 X 10−−19J. Assuming equal spacing between levels, the spacing between energy levels may be approximated by dividing the range of energies by the number of atoms in the crystal.
a. How many copper atoms are in a piece of copper metal in the shape of a cube with edge length 0.5 mm? The density of copper is 8.96 g/cm3.
b. Determine the average spacing in J between energy levels in the copper metal in part (a).
c. Is this spacing larger, substantially smaller, or about the same as the 1 X 10−−18 J separation between energy levels in a hydrogen atom?
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Chapter 12 Solutions
CHEMISTRY THE CENTRAL SCIENCE >EBOOK<
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- Describe the unit cell of lithium (see Figure).arrow_forward8.13 What is the coordination number of atoms in the diamond structure?arrow_forwardConsider the three types of cubic units cells. (a) Assuming that the spherical atoms or ions in a primitive cubic unit cell just touch along the cubes edges, calculate the percentage of occupied space within the unit cell. (Recall that the volume of a sphere is (4/3)r3, where r is the radius of the sphere.) (b) Compare the percentage of occupied space in the primitive cell (pc) with the bcc and fcc unit cells. Based on this, will a metal in these three forms have the same or different densities? If different, in which is it most dense? In which is it least dense?arrow_forward
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