Entropy ($S$) is a measure of the molecular disorder or randomness of a system.

• Dissolution of sugar: Molecules move from a highly ordered crystal lattice into a random distribution in the liquid phase. Disorder increases, so $\Delta S>0$.
• Freezing ($L\to S$), Condensation ($V\to L$), and Deposition ($V\to S$): All involve molecules moving from messy/disordered states to more fixed/ordered states. Disorder decreases, so $\Delta S<0$.