Question

1. Rank the crystal lattice structures in order of decreasingefficiency of space in the structure.
Body centered cubic, face-centered cubic, simple cubic, hexagonalcubic.

2. ou are a researcher for a golf club manufacturer. You are giventwo identical looking cubes of a metal alloy. You are informed thatthey are made of the exact same material, but one is a crystalline,whereas the other is amorphous. It is your job to determine whichone is amorphous because this one is more stress-resistant and isuseful in reinforcing golf clubs. Which of the following is thebest way to determine which is which?

Determinethe density of each cube. The less dense cube is the amorphoussolid. Determinethe density of each cube. The more dense one is the amorphoussolid. Melt bothcubes and look for a broader range of melting temperatures. The onethat melts over a broader range of temperatures is the amorphoussolid. Melt bothcubes and measure the range of melting temperatures. The one thatmelts over a narrower range of temperatures is the amorphoussolid.

Answer 1

Determine the density of each cube. The less dense cube is the amorphous solid.

It is also important to note that many crystals are made from more than one kind of atom. For example, proteins will form crystals under the right conditions, and proteins are more complex than a single metal atom. The unit cell concept applies to protein crystals as it does to single atoms. The unit cell may contain one or more proteins and weigh thousands of atomic mass units. Since it is in the form of a crystal, one of the unit cells will enable you to recreate the entire protein crystal. This fact is exploited when structural biologists perform X-ray crystallography to determine the atomic structures of proteins.