Rührstäbe

Rührstäbe, often translated as stirring rods or stir bars, are essential laboratory equipment used to mix chemicals in a liquid. They are typically small, cylindrical pieces of metal, commonly steel, coated in a non-reactive material such as Teflon (PTFE). This coating prevents corrosion and contamination of the solutions being stirred.

Rührstäbe are used in conjunction with a magnetic stirrer, a device that generates a rotating magnetic field. When a rührstab is placed in a liquid within the stirrer's field, the stirrer's magnetic force causes the rührstab to rotate, thereby agitating and mixing the liquid. They come in various sizes and shapes, including cylindrical, oval, and sometimes with a pivot ring, to suit different vessel geometries and stirring requirements.

The primary function of a rührstab is to ensure homogeneous mixing of solutions, which is crucial for chemical reactions, dissolving solids, and achieving uniform temperatures. They are particularly useful for prolonged stirring periods or when working with volatile or hazardous substances, as they eliminate the need for manual stirring and reduce the risk of exposure. The choice of rührstab size and shape depends on the volume of the liquid, the viscosity of the mixture, and the container's dimensions.