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What fraction of an atom sitting on the “corner” of a 3-dimensional cubic unit cell would be counted as being part of that unit cell?  (For example if you were counting atoms to calculate the theoretical density in that unit cell.)

Shown here is the unit cell for the metal Niobium.  How would you best describe its lattice & basis?     

Most of the mass of an atom is contained within: 

In the 2D lattice above, which of the shape(s) shown is a true unit cell? 

Rank the following bonds in order of increasing bond strength: Hydrogen bonds, Covalent bonds, and van der Waals bonds: 

What contributes to atom-atom repulsion in a solid? 

An orthorhombic unit cell has lattice parameters a = 2 Å, b = 3 Å, and c = 5 Å.  What is the volume of this unit cell?

Which types of orbitals exist in the n = 4 shell?

True or False: To form ionic bonding in LiF, Li should gain an electron to form the anion and F should lose an electron to form the cation.

      Consider the crystal structure for pyrite (FeS2), also known as Fool’s gold, shown here.  Iron atoms are the larger brown spheres, while sulfur atoms are the smaller yellow spheres, as labelled.  This image depicts the cubic unit cell and all atoms shown here are at least PARTIALLY within this unit cell.  Based on this depiction, what is the coordination for the sulfur atoms in this structure?  Note: This is the original structure derived in 1925 and is not entirely accurate, but base your answer on what is shown above.  Hint: All sulfur atoms have the same coordination number, although some may be obscured.