Ionic-Equillibrium-5-By-Prof-Shashank-Deep

1 : Acids and Bases
  • Arrhenius Theory: Defines acids as substances that produce H⁺ ions (protons) in aqueous solutions and bases as substances that produce OH⁻ ions.
  • Brønsted-Lowry Theory: Defines acids as proton (H⁺) donors and bases as proton acceptors.
2 : pH and pOH
  • pH: A measure of the hydrogen ion concentration in a solution.
  • pH = -log[H⁺], where [H⁺] is the hydrogen ion concentration.
  • pOH: A measure of the hydroxide ion concentration in a solution.
  • pOH = -log[OH⁻], where [OH⁻] is the hydroxide ion concentration.
  • For a neutral solution at 25°C, pH + pOH = 14.
3 : Ionization Constant (Ka and Kb)
  • Ka (Acid Dissociation Constant): Measures the extent of ionization of a weak acid.
  • Ka = [H₃O⁺][A⁻] / [HA]
  • Kb (Base Ionization Constant): Measures the extent of ionization of a weak base.
  • Kb = [OH⁻][BH⁺] / [B]
4 : pKa and pKb
  • pKa: The negative logarithm (base 10) of the Ka value. It indicates the strength of an acid.
  • pKa = -log(Ka)
  • pKb: The negative logarithm (base 10) of the Kb value. It indicates the strength of a base.
  • pKb = -log(Kb)
  • pKa + pKb = 14 at 25°C.
5 : Henderson-Hasselbalch Equation
  • Used for buffer solutions.
  • pH = pKa + log([A⁻] / [HA])
6 : Common Ion Effect
  • When a salt is added to a solution that already contains one of the ions from the salt, it reduces the ionization of the weak electrolyte.
7 : Hydrolysis
  • When salts react with water, they can undergo hydrolysis to produce acidic or basic solutions.
  • The extent of hydrolysis depends on the value of the equilibrium constant (Kw) and the ionization constants (Ka and Kb).
8 : Solubility Product (Ksp)
  • Ksp represents the equilibrium constant for the dissolution of a sparingly soluble salt in water.
  • The solubility of a salt depends on the value of Ksp.
9 : Le Chatelier’s Principle
  • When a system at equilibrium is subjected to a change in concentration, temperature, or pressure, it will shift its position to counteract the change.
10 : Buffer Solution
  • Buffers are solutions that resist changes in pH when an acid or base is added.
  • Made by mixing a weak acid and its conjugate base or a weak base and its conjugate acid.
11 : Salt Hydrolysis
  • Salts derived from weak acids and strong bases produce basic solutions.
  • Salts derived from strong acids and weak bases produce acidic solutions.
  • Salts derived from weak acids and weak bases undergo hydrolysis to produce solutions with a pH determined by the relative strengths of the acids and bases involved.
12 : Common Strong Acids and Bases
  • Common strong acids include HCl, H2SO4, HNO3, and HClO4.
  • Common strong bases include NaOH, KOH, and Ba(OH)2.
13 : Autoionization of Water
  • Kw (Ionic Product of Water) at 25°C = 1.0 x 10^-14.
  • Kw = [H₃O⁺][OH⁻].