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⁻].