Beaker (laboratory equipment)

In laboratory equipment, a beaker is generally a cylindrical container with a flat bottom. Most also have a small spout (or "beak") to aid pouring, as shown in the picture. Beakers are available in a wide range of sizes, from one milliliter up to several liters. A beaker is distinguished from a flask by having straight rather than sloping sides. The exception to this definition is a slightly conical-sided beaker called a Philips beaker. The beaker shape in general drinkware is similar.

Beaker

Beakers of several sizes
Uses	Liquid volume containment and measurement
Related items	Laboratory flask

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.

Beakers of different sizes

Construction and use

(A) A low-form or Griffin form beaker
(B) A tall-form or Berzelius beaker
(C) A flat beaker or crystallizer

Philips beaker which can be swirled like a conical flask

Standard or "low-form" (A) beakers typically have a height about 1.4 times the diameter. The common low form with a spout was devised by John Joseph Griffin and is therefore sometimes called a Griffin beaker. 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" (B) beakers have a height about twice their diameter. These are sometimes called Berzelius beakers, after Jöns Jacob Berzelius, and are mostly used for titration. Flat beakers (C) are often called "crystallizers" because most are used to perform crystallization, but they are also often used as a vessel for use in hot-bath heating. These beakers usually do not have a flat scale.

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. Most beakers are accurate to within ~10%.

Standards

DIN EN ISO 3819:2015-12 defines the following types and sizes:

Type	Nominal volume (ml)	Outer diameter (mm) ±5%	Overall height (mm) max.	Wall thickness (mm) min.
Low high beaker	5	22	32	0.7
	10	26	37	0.7
	25	34	52	0.7
	50	42	62	0.8
	100	50	72	0.9
	150	60	82	1.0
	250	70	97	1.1
	400	80	113	1.2
	500	85	118	1.3
	600	90	128	1.3
	800	100	138	1.3
	1000	105	148	1.3
	2000	130	188	1.4
	3000	150	214	1.7
	5000	170	274	2.0
	10000	220	360	2.0
High beaker	50	38	72	0.8
	100	48	82	0.9
	150	54	97	1.0
	250	60	123	1.1
	400	70	133	1.2
	500	79	140	1.3
	600	80	153	1.3
	800	90	178	1.3
	1000	95	183	1.3
	2000	120	244	1.4
	3000	135	284	1.7
	5000	160	324	2.0
Thick wall type	150	60	82	1.11
	250	70	97	1.2
	400	80	111	1.4
	600	90	127	1.4
	1000	105	147	1.4
	2000	132	187	1.5
	5000	170	275	2.5

See also

• Beaker (drinkware)
• Beaker (archaeology)
• Beaker (disambiguation)
• Volumetric flask
• Schott bottle
• Stirring rod
• Test tube
• Graduated cylinder
• Scoop

Further reading

• ASTM E960 - 93 (2008) Standard Specification for Laboratory Glass Beakers

External links

• The dictionary definition of beaker at Wiktionary
• Media related to Beaker (glassware) at Wikimedia Commons