Describe the differences between the face-centered cubic and body-centered cubic crystal structure of transition metals.

The face-centered cubic and body-centered cubic crystal structures of transition metals differ in their arrangement of atoms.

The face-centered cubic (FCC) crystal structure consists of a cube with an atom at each corner and an additional atom in the center of each face. This results in a total of four atoms per unit cell. The body-centered cubic (BCC) crystal structure, on the other hand, consists of a cube with an atom at each corner and an additional atom in the center of the cube. This results in a total of two atoms per unit cell.

The FCC structure has a higher packing efficiency than the BCC structure, with a packing efficiency of 74%. This is because the atoms in the FCC structure are more closely packed together than in the BCC structure. As a result, the FCC structure is more ductile and malleable than the BCC structure.

In terms of properties, the FCC structure is more commonly found in metals that are soft, ductile, and have a low melting point. Examples of metals with an FCC structure include copper, aluminum, and gold. The BCC structure, on the other hand, is more commonly found in metals that are hard, brittle, and have a high melting point. Examples of metals with a BCC structure include iron, tungsten, and chromium.

A-Level Chemistry Tutor Summary: In summary, the main difference between FCC and BCC crystal structures in transition metals lies in atom arrangement and efficiency. FCC structures, with atoms at cube corners and faces, pack more efficiently, making metals like copper and gold soft and ductile. BCC structures, with a central cube atom, result in harder metals like iron, making them less ductile and with higher melting points.