Laboratory flask

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Erlenmeyer flasks from the Argonne National Laboratory. Erlenmeyer Flasks.jpg
Erlenmeyer flasks from the Argonne National Laboratory.

Laboratory flasks are vessels or containers that fall into the category of laboratory equipment known as glassware. In laboratory and other scientific settings, they are usually referred to simply as flasks. Flasks come in a number of shapes and a wide range of sizes, but a common distinguishing aspect in their shapes is a wider vessel "body" and one (or sometimes more) narrower tubular sections at the top called necks which have an opening at the top. Laboratory flask sizes are specified by the volume they can hold, typically in metric units such as milliliters (mL or ml) or liters (L or l). Laboratory flasks have traditionally been made of glass, but can also be made of plastic.


At the opening(s) at top of the neck of some glass flasks such as round-bottom flasks, retorts, or sometimes volumetric flasks, there are outer (or female) tapered (conical) ground glass joints. Some flasks, especially volumetric flasks, come with a laboratory rubber stopper, bung, or cap for capping the opening at the top of the neck. Such stoppers can be made of glass or plastic. Glass stoppers typically have a matching tapered inner (or male) ground glass joint surface, but often only of stopper quality. Flasks which do not come with such stoppers or caps included may be capped with a rubber bung or cork stopper.

Flasks can be used for making solutions or for holding, containing, collecting, or sometimes volumetrically measuring chemicals, samples, solutions, etc. for chemical reactions or other processes such as mixing, heating, cooling, dissolving, precipitation, boiling (as in distillation), or analysis.

List of flasks

There are several types of laboratory flasks, all of which have different functions within the laboratory. Flasks, because of their use, can be divided into:

Many of these flasks can be wrapped in a protective outer layer of glass, leaving a gap between the inner and outer walls. These are called jacketed flasks; they are often used in a reaction using a cooling fluid.

Like many other common pieces of glassware, Erlenmeyer flasks could potentially be used in the production of drugs. In an effort to reduce their proliferation by theft from education institutions where they are commonly stored, some U.S. states (including Texas) have requirements to audit and report unusual inventory discrepancies (not from wear or breakage). Reporting requirements also cover chemicals identified as common starting materials. [1]

Related Research Articles

Erlenmeyer flask

An Erlenmeyer flask, also known as a conical flask or a titration flask, is a type of laboratory flask which features a flat bottom, a conical body, and a cylindrical neck. It is named after the German chemist Emil Erlenmeyer (1825–1909), who created it in 1860.

Laboratory glassware

Laboratory glassware refers to a variety of equipment used in scientific work, and traditionally made of glass. Glass can be blown, bent, cut, molded, and formed into many sizes and shapes, and is therefore common in chemistry, biology, and analytical laboratories. Many laboratories have training programs to demonstrate how glassware is used and to alert first–time users to the safety hazards involved with using glassware.

Florence flask

A Florence Flask/Boiling Flask is a type of flask used as an item of laboratory glassware. It is used as a container to hold liquids. A Florence flask has a round body, a long neck, and often a flat bottom. It is designed for uniform heating, boiling, distillation and ease of swirling; it is produced in a number of different glass thicknesses to stand different types of use. They are often made of borosilicate glass for heat and chemical resistance. Traditional Florence flasks typically do not have a ground glass joint on their rather longer necks, but typically have a slight lip or flange around the tip of the neck. The common volume for a Florence flask is 1 litre.

Test tube

A test tube, also known as a culture tube or sample tube, is a common piece of laboratory glassware consisting of a finger-like length of glass or clear plastic tubing, open at the top and closed at the bottom.

Graduated cylinder Common piece of laboratory equipment used to measure the volume of a liquid

A graduated cylinder, also known as measuring cylinder or mixing cylinder is a common piece of laboratory equipment used to measure the volume of a liquid. It has a narrow cylindrical shape. Each marked line on the graduated cylinder represents the amount of liquid that has been measured.

Fractional distillation is the separation of a mixture into its component parts, or fractions. Chemical compounds are separated by heating them to a temperature at which one or more fractions of the mixture will vaporize. It uses distillation to fractionate. Generally the component parts have boiling points that differ by less than 25 °C (45 °F) from each other under a pressure of one atmosphere. If the difference in boiling points is greater than 25 °C, a simple distillation is typically used.


A bung, stopper or cork is a cylindrical or conical closure used to seal a container, such as a bottle, tube or barrel. Unlike a lid, which encloses a container from the outside without displacing the inner volume, a bung is partially or wholly inserted inside the container to act as a seal.

Volumetric flask

A volumetric flask is a piece of laboratory apparatus, a type of laboratory flask, calibrated to contain a precise volume at a certain temperature. Volumetric flasks are used for precise dilutions and preparation of standard solutions. These flasks are usually pear-shaped, with a flat bottom, and made of glass or plastic. The flask's mouth is either furnished with a plastic snap/screw cap or fitted with a joint to accommodate a PTFE or glass stopper. The neck of volumetric flasks is elongated and narrow with an etched ring graduation marking. The marking indicates the volume of liquid contained when filled up to that point. The marking is typically calibrated "to contain" at 20 °C and indicated correspondingly on a label. The flask's label also indicates the nominal volume, tolerance, precision class, relevant manufacturing standard and the manufacturer's logo. Volumetric flasks are of various sizes, containing from 1 milliliter to 20 liters of liquid.

Rainer Ludwig Claisen

Rainer Ludwig Claisen was a German chemist best known for his work with condensations of carbonyls and sigmatropic rearrangements. He was born in Cologne as the son of a jurist and studied chemistry at the university of Bonn (1869), where he became a member of K.St.V. Arminia. He served in the army as a nurse in 1870–1871 and continued his studies at Göttingen University. He returned to the University of Bonn in 1872 and started his academic career at the same university in 1874. He died in 1930 in Godesberg am Rhein.

Ground glass Glass with roughened surface

Ground glass is glass whose surface has been ground to produce a flat but rough (matte) finish, in which the glass is in small sharp fragments.

Flask may refer to:

Dropping funnel

A dropping funnel is a type of laboratory glassware used to transfer fluids. They are fitted with a stopcock which allows the flow to be controlled. Dropping funnels are useful for adding reagents slowly, i.e. drop-wise. This may be desirable when the quick addition of the reagent may result in side reactions, or if the reaction is too vigorous.

Beaker (laboratory equipment)

In laboratory equipment, a beaker is generally a cylindrical container with a flat bottom. Most also have a small spout 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.


A Fleaker is a brand of container for liquids used in the laboratory. It can be described as a cross between the Griffin beaker and the Erlenmeyer flask.

Round-bottom flask

Round-bottom flasks are types of flasks having spherical bottoms used as laboratory glassware, mostly for chemical or biochemical work. They are typically made of glass for chemical inertness; and in modern days, they are usually made of heat-resistant borosilicate glass. There is at least one tubular section known as the neck with an opening at the tip. Two or three-necked flasks are common as well. Round bottom flasks come in many sizes, from 5 mL to 20 L, with the sizes usually inscribed on the glass. In pilot plants even larger flasks are encountered.

Schlenk line Glass apparatus used in chemistry

The Schlenk line is a commonly used chemistry apparatus developed by Wilhelm Schlenk. It consists of a dual manifold with several ports. One manifold is connected to a source of purified inert gas, while the other is connected to a vacuum pump. The inert-gas line is vented through an oil bubbler, while solvent vapors and gaseous reaction products are prevented from contaminating the vacuum pump by a liquid-nitrogen or dry-ice/acetone cold trap. Special stopcocks or Teflon taps allow vacuum or inert gas to be selected without the need for placing the sample on a separate line.

Schlenk flask

A Schlenk flask, or Schlenk tube is a reaction vessel typically used in air-sensitive chemistry, invented by Wilhelm Schlenk. It has a side arm fitted with a PTFE or ground glass stopcock, which allows the vessel to be evacuated or filled with gases. These flasks are often connected to Schlenk lines, which allow both operations to be done easily.

Ground glass joint Used in laboratories to quickly and easily assemble apparatus from available parts

Ground glass joints are used in laboratories to quickly and easily fit leak-tight apparatus together from commonly available parts. For example, a round bottom flask, Liebig condenser, and oil bubbler with ground glass joints may be rapidly fitted together to reflux a reaction mixture. This is a large improvement compared with older methods of custom-made glassware, which was time-consuming and expensive, or the use of less chemical resistant and heat resistant corks or rubber bungs and glass tubes as joints, which took time to prepare as well.

Air-free techniques refer to a range of manipulations in the chemistry laboratory for the handling of compounds that are air-sensitive. These techniques prevent the compounds from reacting with components of air, usually water and oxygen; less commonly carbon dioxide and nitrogen. A common theme among these techniques is the use of a fine (100-10−3 Torr) or high (10−3-10−6 Torr) vacuum to remove air, and the use of an inert gas: preferably argon, but often nitrogen.

Laboratory drying rack

Laboratory drying rack is a pegboard for hanging and draining glassware in a laboratory. It is available in different varieties and sizes. It can be used for different materials of glassware in the laboratory room such as funnels, pipettes, mixing balls, slides, bottle stoppers, tubing and so on. In addition to that, the pegs on the drying rack are easily removable and replaceable in order to maintain the cleaning of the lab racks to avoid contamination with other apparatus used on the same rack. Any common laboratory needs to have at least two or three drying racks per lab.


  1. "Memorandum of Understanding between the Texas Department of Public Safety and the Texas Higher Education Coordinating Board" (PDF). 080107

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