Mnemonic 1: Four Colligative Properties — "VP-B-F-O"

Vapour pressure lowering → Pressure goes down Boiling point → Goes up (B for Both up and Boiling) Freezing point → Goes down (F for Falling) Osmotic pressure → Observed

All depend on NUMBER of particles, not NATURE.

Mnemonic 2: Positive vs Negative Deviation — "PEN"

Positive deviation = Ethanol + water = Not ideal Remember: "Positive = Ethanol, Negative = Not ethanol ($CHCl_{3}$+acetone)"

• Positive: Pressure UP → Partial pressures exceed Raoult → Minimum boiling azeotrope
• Negative: Negative = $CHCl_{3}$ + aCetone = Near maximum boiling

Mnemonic 3: Van't Hoff Factor Direction

"Dissociation → Doubles (or more) → i > 1" "Association → Aggregate → i < 1" Or: DID: Dissociation Increases to Diminish freezing point more.

Mnemonic 4: Kf vs Kb for Water — "Frozen is Faster"

"Kf (1.86) > Kb (0.52) for water" Remember: Frozen = Faster drop (1.86) vs Boil = Barely (0.52) Ratio: Kf/Kb ≈ 3.5. So freezing point depression is 3.5× more sensitive than boiling point elevation.

Mnemonic 5: Camphor in Cryoscopy — "Camphor = Champion"

Camphor Kf = 40.0 (Champion value — largest). This "champion" cryoscopic constant makes it ideal for molar mass determination.

Mnemonic 6: Van't Hoff Factors for Common Electrolytes

"NaCl = 2, $CaCl_{2}$ = 3, $AlCl_{3}$ = 4" — each adds one more ion (Cl count matches i − 1!): NaCl → 1Cl → i=2; $CaCl_{2}$ → 2Cl → i=3; $AlCl_{3}$ → 3Cl → i=4. Trick: i = number of Cl atoms in formula + 1 (for chloride salts with single-charge cation and no sulfate).

Mnemonic 7: Henry's Law Temperature Effect — "Hot water loses its fizz"

Warm soda goes flat → K_H increases with temperature → gas solubility decreases. "Hot coffee doesn't fizz" — gases escape hot liquids.

Mnemonic 8: Osmotic Pressure Units

π = C R T → units: (mol/L) × (L·atm/mol·K) × (K) = atm ✓ "CRT = Cathode Ray Tube = pressure in a tube (atm)"