boilling

Boiling is a phase transition process where a substance in a liquid state changes to a gaseous state due to an increase in temperature and pressure. It occurs when the vapor pressure of the liquid equals the surrounding atmospheric pressure. At this point, the liquid starts to form bubbles of vapor within its bulk, which then rise to the surface and escape.

The temperature at which boiling occurs is called the boiling point. This point is specific to each substance at a given pressure. For water at standard atmospheric pressure (1 atmosphere or 101.325 kilopascals), the boiling point is 100 degrees Celsius or 212 degrees Fahrenheit. Changes in pressure affect the boiling point; for example, at higher altitudes where atmospheric pressure is lower, water boils at a lower temperature. Conversely, in a pressure cooker, where pressure is increased, water boils at a higher temperature.

Boiling is a form of vaporization. Unlike evaporation, which occurs only at the surface of a liquid, boiling happens throughout the entire volume of the liquid. The process requires energy, known as the latent heat of vaporization, to overcome the intermolecular forces holding the liquid molecules together and convert them into a gas. Boiling is a common phenomenon encountered in cooking, industrial processes, and various scientific experiments.