The defect that occurs due to a displacement of an ion is known as……………a.Vacancy defectb.Frankel defectc.Schottky defectd.Impurity defect

The defect that occurs due to a displacement of an ion is known as a Frankel defect.

Here's a step-by-step explanation:

1. In a crystal lattice, atoms or ions occupy specific positions. However, sometimes, an ion might not be in its correct place, leading to a defect.

2. This displacement of an ion from its normal position creates an interstitial site, where the ion is out of place, and a vacancy, where the ion should have been.

3. This type of defect is named after the scientist who first described it, Jacob Frankel.

4. Therefore, the defect that occurs due to a displacement of an ion is known as a Frankel defect.