Freundlich and Langmuir adsorption isotherms
Surface Chemistry and Colloids · Chemistry
Study notes
Adsorption data: at P = 1 atm, x/m = 2; at P = 4 atm, x/m = 4. Find Freundlich 1/n. Step 1: x/m = kP^(1/n). Take logs: log(x/m) = log k + (1/n)log P. Step 2: Point 1: log 2 = log k + (1/n)(0) → log k = log 2. Step 3: Point 2: log 4 = log 2 + (1/n)log 4. Step 4: (1/n) = (log 4 − log 2)/log 4 = log 2/log 4 = 0.5. 1/n = 0.5: favourable adsorption, pressure helps but with diminishing returns.