Final answer:
The slip plane in a crystal structure refers to the plane having the b) most dense atomic packing.
Step-by-step explanation:
The slip plane in a crystal structure refers to the plane having the most dense atomic packing. This is because the slip plane allows for easier movement of atoms or dislocation in the crystal lattice, which is crucial for the process of plastic deformation. The slip plane can be visualized as the plane along which layers of atoms can easily slide past each other.
For example, in a face-centered cubic (FCC) crystal structure, the {111} planes are the slip planes because they have the highest atomic packing density. On the other hand, the {100} planes in FCC structures have the lowest atomic packing density and are less likely to be slip planes.
Understanding the slip planes and their densities is important in studying the mechanical properties and behavior of materials.