Plastic Beakers with Spout – A beaker in a laboratory equipment, is generally a cylindrical container with a flat bottom. Most also have a small spout to aid pouring. Beakers are available in a wide range of sizes, from one millilitre up to several litres.
Plastic beakers with spout is distinguished from a flask by having straight rather than sloping sides.
Beakers are commonly made of glass (today usually borosilicate glass, but can also be in metal (such as stainless steel or aluminum) or certain plastics (notably polythene, polypropylene, PTFE).
A common use for polypropylene beakers is gamma spectral analysis of liquid and solid samples.
Uses
Low form beakers typically have a height about 1.4 times the diameter, the common low form with a spout. These are the most universal character and are used for various purposes—from preparing solutions and decanting supernatant fluids to holding waste fluids prior to disposal to performing simple reactions. Low form beakers are likely to be used in some way when performing a chemical experiment. Tall-form beakers have a height about twice their diameter. These are sometimes called Berzelius beakers and are mostly used for titration.
The presence of a spout means that the beaker cannot have a lid. However, when in use, beakers may be covered by a watch glass to prevent contamination or loss of the contents, but allowing venting via the spout. Alternatively, a beaker may be covered with another larger beaker that has been inverted, though a watch glass is preferable.
Beakers are often graduated, that is, marked on the side with lines indicating the volume contained. For instance, a 250 mL beaker might be marked with lines to indicate 50, 100, 150, 200, and 250 mL of volume. These marks are not intended for obtaining a precise measurement of volume (a graduated cylinder or a volumetric flask would be a more appropriate instrument for such a task), but rather an estimation.