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Saturday, 31 October

JEE Main · Chemistry · Environmental Chemistry

Water Quality BOD and COD

JEE Main asked Water Quality BOD and COD 5 times in 5 of the 108 shifts Lumi analysed, in 2020, 2021, 2022 and 2023. It belongs to Environmental Chemistry (Chemistry). The longest wait between two years asking it was 1 year. In 2022 it came in more than one shift of the same year.

Updated 2026-10-24

Times asked
5
in 5 shifts
Years
4 of 8
First asked
2020
last in 2023
Pattern
Comes in cycles
across the analysed shifts

Questions on this idea a shift, by year

2017–2026. Asked in 2020, 2021, 2022 and 2023. Years differ in how many shifts Lumi analysed, so each year is scaled to one shift of 25 Chemistry questions.

00.050.10’170.08’200.03’210.07’220.07’230’240’250’26

Raw count: 2017: 0 in 1 shift · 2020: 1 in 12 shifts · 2021: 1 in 24 shifts · 2022: 2 in 24 shifts · 2023: 1 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
  • 20231 of 12
  • 20222 of 24
  • 20211 of 24
  • 20201 of 12
  • 20170 of 1

Asked in that shift More than once Not asked

How JEE Main framed it

Single correct is the usual form. Skill tested: recall.

  • Statement i/ii on water quality parameters
  • Definition recall

Difficulty

Easy 3Medium 2Hard 0

Every question was multiple choice.

Every question

All 5 questions

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

  1. 11 Apr 2023, Shift 1 · Q71Given below are two statements: Statement I: If BOD is 4 ppm and dissolved oxygen is 8 ppm, then it is a good quality water. Statement II:…MediumTwo statements
  2. 26 Jun 2022, Shift 2 · Q70The measured BOD values for four different water samples (A-D) are as follows: A = 3 ppm; B=18 ppm; C=21 ppm; D=4 ppm. The water samples…EasySingle correct
  3. 25 Jun 2022, Shift 2 · Q72Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R. Assertion A: Polluted water may have…MediumAssertion–reason
  4. 24 Feb 2021, Shift 2 · Q41Given below are two statements : Statement I :\textbf{Statement I :} The value of the parameter “Biochemical Oxygen Demand (BOD)” is important for…EasyTwo statements
  5. 9 Jan 2020, Shift 2 · Q38Biochemical Oxygen Demand (BOD) is the amount of oxygen required (in ppm) :EasySingle correct

Shifts: 9 Jan 2020, Shift 2, 24 Feb 2021, Shift 2, 25 Jun 2022, Shift 2, 26 Jun 2022, Shift 2, 11 Apr 2023, Shift 1.

Same topic

Other ideas in Environmental Chemistry

Environmental Chemistry has 19 ideas JEE Main has asked; 15 of them came up in more than one question. The 12 most asked are below.

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