Boiling: It is a bulk phenomenon. Particles from bulk (whole) of the liquid change into vapour state. Boiling point: The constant temperature at which a liquid changes into gas/vapour is known as its boiling point. Boiling point of water is 100°C or (273 + 100) = 373 K. Condensation point of gas also depends upon the surrounding pressure. More will be the pressure more closer will be molecules and thus greater will be the inter-molecular forces of attraction. Thus more will be the surrounding pressure more easily gas gets condensed in to liquid. Difference between Boiling and Evaporation: (i) Boiling takes place only at a particular temperature for a liquid. Whereas evaporation occurs at all temperatures. (ii) Boiling is Bulk phenomena i.e., the bubble formation occurs even below the surface. Whereas evaporation is surface phenomena, i.e., bubble formation occurs only on the surface of liquid.