Le Chatelier's principle

The chemist Henry Louis Le Châtelier (1850-1936) was the first to notice that various phenomena in thermochemistry obeyed a principle that can be stated as follows: "If the thermodynamic conditions (pressure, temperature, concentration) of a system at equilibrium are modified, the system reacts to partially oppose the changes imposed until a new equilibrium is reached."

The German Nobel physics prize winner Karl Ferdinand Braun (1850-1918) also discovered this principle, which is sometimes called the Le Chatelier-Braun principle.