Learn

Friday, 9 October

JEE Main 2020 · ChemistryMultiple choiceSingle correctEasyRecall

JEE Main 9 January 2020, Shift 2, Chemistry Q38

Question 38 of 75 in this shift, Chemistry question 13 of 25, Section A.

Biochemical Oxygen Demand (BOD) is the amount of oxygen required (in ppm) :
  1. (1)for sustaining life in a water body.
  2. (2)for the photochemical breakdown of waste present in 1 m3^3 volume of a water body.
  3. (3)by bacteria to break-down organic waste in a certain volume of a water sample.Official answer
  4. (4)by anaerobic bacteria to breakdown inorganic waste present in a water body.

Official answer

Option 3

NTA final key (Jan 2020).

Chapter
Environmental Chemistry
Topic
Environmental Chemistry
Idea tested
Water Quality BOD and COD

Same idea in other shifts

Asked 2× in all
  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

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.