Solutions and Colligative Properties for JEE

• Colligative properties depend on the number of solute particles
• Positive deviation: weaker A–B attraction; negative deviation: stronger
• Electrolytes raise i above 1; association lowers it
• Azeotropes boil at constant composition

• Raoult: p = p°χ
• Relative lowering: Δp/p° = χ_solute
• ΔT_b = iK_b m, ΔT_f = iK_f m
• Osmotic pressure π = iCRT

Printable Solutions and Colligative Properties formula sheet: formulas, key ideas and traps on one page. Save it as a PDF for offline revision.

• Forgetting i for electrolytes
• Using molarity in ΔT formulas (use molality)
• Unit errors in osmotic pressure

Appears frequently. One numerical is common. Practise i for strong and weak electrolytes.

Prerequisites: Mole Concept and Stoichiometry.

Chapter names follow the current rationalised NCERT textbooks. Read these sections before solving PYQs.

Question. A 0.1 molal aqueous solution of a weak acid HA shows a freezing point depression of 0.2046°C. When 100 g of this solution (containing 100 g of water) is placed in a closed container alongside a beaker containing 100 g of pure water at 25°C, water vapor transfers between them until equilibrium is reached. Find (a) the degree of dissociation of HA, and (b) the final mass of the solution that originally contained HA. (Kf for water = 1.86 K kg/mol)

This example was solved twice independently and both solutions agree.

Full-chapter free lectures picked from YouTube search results by views, from established JEE channels (mostly in Hinglish). Use the subtopic list to jump straight to the part you need (timestamps come from each video's own chapter list). Watch one, then solve PYQs the same day.

• SOLUTIONS in One Shot - Full Chapter Revision | Class 12 | JEE Main — JEE Wallah, 1:46:30
  Jump to a subtopic (26)

  • 00:00 Introduction
  • 01:16 Vapour Pressure
  • 03:23 Factors Affecting Vapour Pressure
  • 04:35 Question
  • 06:03 Raoult's Law (For two Volatile Liquid)
  • 13:10 Raoult's Law (When Solute is Non Volatile)
  • 17:31 Types Of Solution(Ideal And Non ideal)
  • 25:38 Graph of ideal and Non-Ideal
  • 29:41 Examples of ideal/Non-ideal
  • 33:33 Azeotropic Mixture
  • 36:57 Mole Fraction in Vapour Phase
  • 39:14 Colligative Property
  • 39:58 RLVP(Relative Lowering in Vapour Pressure)
  • 44:17 EBP(Elevation in Boiling Point)
  • 51:11 DFP(Depression in Freezing Point)
  • 57:13 Osmotic Pressure
  • 1:04:09 Types Of Solutions (Isotonic, Hypotonic, Hypertonic)
  • 1:06:21 Van't Hoff Factor and Abnormal Molecular Mass
  • 1:10:51 Calculation of i (Van't Hoff Factor) for association and dissociation.
  • 1:14:33 Questions
  • 1:15:46 Colligative Property Formula(Imp. for Exam)
  • 1:17:50 Questions
  • 1:30:26 PYQs
  • 1:36:35 Henry's Law
  • 1:39:18 PYQs
  • 1:44:15 Thank You
• SOLUTIONS in 1 Shot - All Concepts Covered || JEE Main & Advanced || Class 12 — Lakshya JEE, 4:12:30
  Jump to a subtopic (20)

  • 00:00 Introduction
  • 02:18 Solution
  • 06:36 Types of solution
  • 15:16 Molarity
  • 26:18 Molality
  • 38:07 Mole fraction
  • 45:04 Percentage concentration
  • 1:25:13 Vapour pressure of pure liquid
  • 1:46:54 Solution of a non-volatile solute in volatile solvent
  • 1:51:31 Raoult’s law
  • 1:56:06 Solution of volatile solute in volatile solvent
  • 2:04:07 Composition of vapour phase
  • 2:13:47 Ideal solution
  • 2:19:21 Non-ideal solution
  • 2:37:43 Distillation
  • 2:54:07 Azeotropic mixture
  • 2:58:58 Colligative properties
  • 3:59:30 Solubility of a gas in liquid and Henry’s constant
  • 4:12:06 Thank You Bacchon
  • 4:16:30 Thank You Bacchon

• 13 JEE Main 2026 PYQs on Solutions and Colligative Properties, with solutions.
• Read the chapter in NCERT textbooks (official, free), then solve its NCERT Exemplar (official, free) questions.
• Chapter-wise past questions: JEE Main and Advanced PYQs and question bank.
• Timed practice tests: NTA Abhyas practice tests (official, free) and our free mock tests.
• See it move: interactive simulation.