Which term describes a point defect created when an atom is missing from its original position in the crystal lattice?

Which term describes a point defect created when an atom is missing from its original position in the crystal lattice?

• A. A missing entire layer in a crystal.
• B. A point defect created when an atom is missing from its original position in the crystal lattice.
• C. An extra atom in the lattice.
• D. A dislocation within a crystal.

Answer: (B)

A vacancy defect. This is a point defect where a lattice site is empty because an atom is missing from its position in the crystal, exactly matching the described situation. It’s the simplest type of point defect and can influence diffusion and material properties. The other descriptions refer to different defect types: a missing entire layer describes a larger-scale planar defect, a lattice with an extra atom is an interstitial defect, and a dislocation is a line defect.

A vacancy defect. This is a point defect where a lattice site is empty because an atom is missing from its position in the crystal, exactly matching the described situation. It’s the simplest type of point defect and can influence diffusion and material properties. The other descriptions refer to different defect types: a missing entire layer describes a larger-scale planar defect, a lattice with an extra atom is an interstitial defect, and a dislocation is a line defect.