JEE Main · Chemistry · The Solid State

Frenkel Defect

JEE Main asked Frenkel Defect 2 times in 2 of the 108 shifts Lumi analysed, all in 2021. It belongs to Solid State Defects, in The Solid State (Chemistry). In 2021 it came in more than one shift of the same year.

Updated 2026-10-24

Times asked: 2; in 2 shifts
Years: 1 of 8
First asked: 2021; the only year
Pattern: Gone quiet; across the analysed shifts

Questions on this idea a shift, by year

2017–2026. Asked in 2021. Years differ in how many shifts Lumi analysed, so each year is scaled to one shift of 25 Chemistry questions.

Raw count: 2017: 0 in 1 shift · 2020: 0 in 12 shifts · 2021: 2 in 24 shifts · 2022: 0 in 24 shifts · 2023: 0 in 12 shifts · 2024: 0 in 18 shifts · 2025: 0 in 8 shifts · 2026: 0 in 9 shifts.

Shift by shift

Each square is one analysed shift, in date order. Open a filled one for that paper.

20260 of 9
20250 of 8
20240 of 18
20230 of 12
20220 of 24
20212 of 24
20200 of 12
20170 of 1

Asked in that shift More than once Not asked

How JEE Main framed it

Match the list is the usual form. Skill tested: conceptual.

Statement i/ii on solid state defects
Match list on crystal defects and examples

Difficulty

Easy 1Medium 1Hard 0

Every question was multiple choice.

Every question

All 2 questions

From the official JEE Main shift papers, newest first. Open one for the full question, the options and the official answer.

Shifts: 4 Aug 2021, Shift 1, 26 Aug 2021, Shift 1.

Same topic

Other ideas in Solid State Defects

Solid State Defects has 7 ideas JEE Main has asked; 2 of them came up in more than one question.

Band Theory of Solids2× · 2024
Non-Stoichiometric Composition Calculationsonce · 2022
Schottky Defectonce · 2022
Impurity Defects and Dopingonce · 2021
Magnetic Propertiesonce · 2021
AgBr Dual Defect Exceptiononce · 2020

Topic analysis Chapter analysis All repeated ideas