JEE Main Chemistry · Thermodynamics (Chemistry)

Enthalpy of Phase Transitions

Enthalpy of Phase Transitions (Thermodynamics (Chemistry)) was asked 3 times in 3 JEE Main shifts, 2022–2025, out of the 42 shifts Lumi analysed. 1 of the 3 had a numerical answer.

Times asked: 3; in 3 shifts
Years: 2022–2025
Usual format: Numerical value; Calculation
Pattern: Occasional; repeats across shifts

How it is asked

Statement i/ii on melting of ice
Total enthalpy change over heating and phase change

Difficulty

Easy 2Medium 1Hard 0

Where it sits

Chapter: Thermodynamics (Chemistry). Topic: Enthalpy and Hess's Law, 24 questions over 14 ideas.

All 3 questions

Newest first, each with its options and official answer.

3 Apr 2025, Shift 2 · Q53Given below are two statements: Statement I : When a system containing ice in equilibrium with water (liquid) is heated, heat is absorbed…EasyTwo statements
7 Apr 2025, Shift 1 · Q53Total enthalpy change for freezing of 1 mol of water at $10^\circ$ C to ice at $-10^\circ$ C is __________ (Given: $\Delta_{fus}H = x$ …MediumSingle correct
29 Jun 2022, Shift 1 · Q8217.0 g of $\mathrm{NH_3}$ completely vapourises at $-33.42^\circ\mathrm{C}$ and 1 bar pressure and the enthalpy change in the process is…EasyNumerical value