JEE Main 2021 · ChemistryNumerical answerNumerical valueEasyCalculation

JEE Main 25 July 2021, Shift 1, Chemistry Q55

Question 55 of 90 in this shift, Chemistry question 25 of 30, Section B.

At 298 K, the enthalpy of fusion of a solid (X) is 2.8 kJ mol

^{-1}

and the enthalpy of vaporisation of the liquid (X) is 98.2 kJ mol

^{-1}

. The enthalpy of sublimation of the substance (X) in kJ mol

^{-1}

is _________. (in nearest integer)

Official answer

101

NTA final key.

Chapter: Thermodynamics (Chemistry)
Topic: Enthalpy and Hess's Law
Idea tested: Enthalpies of Phase Transitions

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