Beakers, also known as chemistry beakers, are cylindrical, flat-bottomed vessels for mixing, analyzing, and transporting liquids, and often have a reinforced rim with a spout for pouring. They can be made of glass, plastic, or metal. Depending on the material of their construction, they may be used for heating and containing chemical reactions. Among the factors for choosing the best beaker for a specific application are the degree of chemical, heat, and corrosion resistance provided by the material, as well as the capacity, autoclavability, surface finish, and clarity. Other features may include handles, a spout or multiple spouts, a marking area for labeling, and a lid.
In general, glass beakers provide clarity and strength, and borosilicate glass in particular withstands temperature changes to resist cracking. Some are made of Pyrex, which is a brand of borosilicate glass. Plastic beakers are impact resistant. Different types of plastic such as PTFE, polypropylene, polycarbonate, and polyethylene are compatible with various substances. Stainless steel and aluminum beakers are durable and won't shatter.
The style or form of a beaker may also lend itself to specific applications. A standard beaker, also known as Griffin or low-form, is the most commonly used and has a lower overall height than a Berzelius beaker, also known as high-form, which is used mainly for titration. A third form has a shallow, wide structure and is used for liquid crystallization.
Many beakers have graduations that are printed, etched, or molded on the sides for approximating volume. For measurement applications, a graduated cylinder, pipette, or volumetric flask provides greater accuracy. Beakers and flasks are two of the most common labware vessels. Both have a conical base, but whereas as the sides of a beaker form a straight cylinder that results in a wide mouth, the sides of a flask taper to form a slim neck. Certain beakers are manufactured to meet specific industry standards, such as ASTM E960 specifications for standard dimensional requirements for laboratory glass beakers. Beakers are used by scientists, researchers, and educators for chemistry and other scientific applications.