IIT JEE Chemistry Practice Paper – Part 18: Ionic Equilibrium with Notes
Topic: Ionic Equilibrium Type: Multiple Choice Questions (MCQs) Marks: +4 for each correct answer Negative Marking: 0 (Practice Mode) The pH of 0.001 M HCl solution is: 1 2 3 4 Which of the following is a strong electrolyte? CH3COOH NH4OH NaCl H2CO3 For a weak acid HA, the degree of dissociation (α) in dilute solution is given by: α = √(Ka / C) α = Ka / C α = C / Ka α = √(C / Ka) The pH of 0.01 M NaOH solution at 25°C is approximately: 2 10 12 14 The value of ionic product of water (Kw) at 25°C is: 1 × 10–7 1 × 10–10 1 × 10–12 1 × 10–14 Which one of the following represents a buffer solution? HCl + NaCl CH3COOH + CH3COONa NaOH + NaCl NH4Cl + NaCl The solubility of AgCl will decrease in presence of NaCl due to: Common ion effect Hydrolysis Oxidation Reduction The pH of a neutral solution at 40°C will be: 7.0 Less than 7.0 Greater than 7.0 Infinite The solubility product (Ksp) expression for CaF2 is: [Ca²⁺][F⁻] [Ca²⁺][F⁻]² [Ca²⁺]²[F⁻] [Ca²⁺]²[F⁻]² If the pH of a solution is 5, the concentration of H⁺ ions is: 1 × 10–3 M 1 × 10–4 M 1 × 10–5 M 1 × 10–6 M Submit Answers Ionic Equilibrium: The Dance of Ions in Solution A Strategic Guide for IIT-JEE Aspirants by Prof. Anil Tyagi Future engineers, welcome. While chemical equilibrium deals with molecules, Ionic Equilibrium unveils the dynamic world of ions in solution—a realm critical for understanding everything from blood chemistry to industrial processes. This topic is a cornerstone of physical chemistry for JEE, demanding both conceptual clarity and numerical agility. Our goal is to master the behavior of acids, bases, and salts when they dissociate in water. 1. The Foundation: Electrolytes & Degree of Dissociation 2. Acid-Base Theories: The Evolving Definition 3. The Core of Quantitative Analysis: pH and pOH The power of these concepts lies in their logarithmic scale, which converts cumbersome numbers into manageable values. 4. Calculating pH for Different Scenarios This is a high-frequency question in JEE. You must be able to identify the system and apply the correct formula. 5. The Guardians of pH: Buffer Solutions A buffer solution resists a change in pH upon the addition of small amounts of acid or base. They are indispensable in biological systems. 6. The Solubility Equilibrium: When Precipitates Form This tells us whether a salt will dissolve or precipitate under given conditions. Key Relationship: For a 1:1 electrolyte like AgCl, Solubility (S) = √K_sp. The relationship becomes more complex for other stoichiometries (e.g., for A₂B₃, K_sp = 108 S⁵). Professor Tyagi’s Key Takeaways for JEE Success: Master these principles. Ionic Equilibrium is not about memorization; it’s about applying a logical framework to predict the behavior of ions in solution. Your clarity of concept here will be the common ion that precipitates your success in JEE. – Prof. Anil Tyagi









