Arrange in increasing order of acidity: CH₃CH₂CH₂COOH, CH₃CHClCOOH, CH₃COOH.
Acidity increases with electron-withdrawing groups: CH₃CH₂CH₂COOH (alkyl) < CH₃COOH < CH₃CHClCOOH (Cl closer to COOH).
Ref: NCERT Class 12 Chemistry > Chapter 12: Aldehydes, Ketones and Carboxylic Acids > Topic: Chemical Reactions - Reduction, Oxidation and Tests - Tollens, Fehling, Iodoform