JEE Main 2023 · ChemistryNumerical answerNumerical valueEasyCalculation

JEE Main 12 April 2023, Shift 1, Chemistry Q81

Question 81 of 90 in this shift, Chemistry question 21 of 30, Section B.

At 600K, the root mean square (rms) speed of gas X (molar mass = 40) is equal to the most probable speed of gas Y at 90K. The molar mass of the gas Y is ______ g mol

^{-1}

.(Nearest integer)

Official answer

NTA final key.

Chapter: States of Matter
Topic: Ideal Gas Laws
Idea tested: Gas Molecular Velocity Ratios

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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.