Rotary evaporator, is a laboratory instrument used for the efficient and gentle removal of solvents from liquid mixtures by evaporation. The basic setup consists of a motor-driven rotary evaporation flask (often called a "rotating flask" or "rotavap flask"), connected to a vacuum pump and a condenser. The liquid mixture to be concentrated is placed in the rotating flask, and as the flask rotates, the solvent evaporates due to reduced pressure created by the vacuum pump and is condensed back into liquid form by the condenser. The concentrated sample can then be collected in a separate container. Rotavaps are commonly used in organic chemistry laboratories for solvent removal, concentration of samples, and purification of compounds. They are especially useful for handling sensitive or volatile compounds that may degrade under high temperatures.