Surface Tension and Contact Angle

This lecture covers the concepts of surface tension, contact angle, and wetting phenomena at both macroscopic and molecular scales. It discusses the Young equation, wetting behaviors, and the effects of surface modifications on contact angles. The lecture also explores surface tension in nanoparticles, the melting behavior of nanoparticles, and the stability of small nanoparticles based on 'magic numbers'. Examples of surface tension in everyday scenarios are provided, along with experimental results and theoretical considerations. The instructor emphasizes the intermolecular forces and surface energies that govern these phenomena.