JEE Main 2021 · PhysicsMultiple choiceSingle correctMediumMulti-step

JEE Main 31 August 2021, Shift 2, Physics Q7

Question 7 of 90 in this shift, Physics question 7 of 30, Section A.

A mixture of hydrogen and oxygen has volume

500

^3

, temperature

300

K, pressure

400

kPa and mass

0.76

g. The ratio of masses of oxygen to hydrogen will be :

(1) $3:8$
(2) $8:3$
(3) $3:16$
(4) $16:3$ Official answer

Official answer

Option 4

NTA final key.

Chapter: Kinetic Theory
Topic: Ideal Gas Laws
Idea tested: Ideal Gas Equation

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Asked 10× in all

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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 108 of the 174 JEE Main shifts held from 2017 to 2026.