NationMaster - Encyclopedia: Volumetric flask

A volumetric flask (vol flask for short) is a type of laboratory flask (piece of laboratory glassware) used to contain or measure a very precise and accurate amount of a liquid. It is shaped like a Florence flask with a flatter bottom so as to not tip over. The single, rather long, narrow neck is marked (usually by a circumferential scratch or etch on the glass) at a very precise measurement. When the liquid has been added to that point (so the bottom of the meniscus is on the line), it is usually accurate to within a small fraction of a percent and highly precise. However, a single flask can usually only be used for a certain measurement, e.g. a 250.00 mL flask can only be used to measure 250 mL. The volume mark is usually made by machine, so it can be more assuredly accurate than a hand-made mark. Image File history File linksMetadata Download high-resolution version (650x1666, 236 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Volumetric flask Laboratory flask Metadata This file contains additional information, probably added from the digital camera or scanner... Image File history File linksMetadata Download high-resolution version (650x1666, 236 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Volumetric flask Laboratory flask Metadata This file contains additional information, probably added from the digital camera or scanner... Erlenmeyer flasks from the Argonne National Laboratory glassblowing shop. ... Brown glass jars with some clear lab glassware in the background Laboratory glassware refers to a variety of equipment, traditionally made of glass, used for scientific experiments and other work in science, especially in chemistry and biology laboratories. ... In Wikipedia, precision has the following meanings: In engineering, science, industry and statistics, precision characterises the degree of mutual agreement among a series of individual measurements, values, or results - see accuracy and precision. ... A Center for Correct, Usable, Reliable, Auditable, and Transparent Elections ACCURATE was established by a group of computer scientists, psychologists and policy experts to address problems with electronic voting. ... A liquid will usually assume the shape of its container. ... Florence flask A Florence flask (also known as a round bottom flask or a boiling flask) is a piece of laboratory glassware. ... Meniscus (plural: menisci), from the Greek for crescent, has different meanings: // Meniscus in liquids A: Read the bottom of a concave meniscus. ... The millilitre (ml or mL, also spelt milliliter) is a metric unit of volume that is equal to one thousandth of a litre. ...

The use of a volumetric flask almost always involves containing a certain amount of a liquid, either for making solutions or diluting a liquid to the size of the flask. This is done by adding the solvent (or the liquid to be measured) to the flask until it reaches the neck, at which point it is usually added much more slowly, via pipette or dropper depending on the size of the flask. One must be careful not to add more than the amount the flask is supposed to measure; if one does so, the process may need to be repeated. This can be problematic, especially when working with expensive chemicals. If a dilution is called for, the completely-filled flask is then stoppered and inverted several times. Dissolving table salt in water This article is about a chemical solution; for other uses of the term solution, see solution (disambiguation). ... Dilute is an indie rock band from Fremont, California. ... For other uses, see Solvent (disambiguation). ... A selection of pipettes A pipette (also called a pipet or a pipettor) is a laboratory instrument used to transport a measured volume of liquid. ... A dropper is a program that has been designed or modified to install a virus onto the target system. ...

Volumetric flasks are often marked TC meaning "To Contain", often with a certain temperature at which the volume measurement is most accurate. TC means that when filled to the circumferential mark on the neck, the flask will contain the designated amount of liquid, as opposed to TD (To Deliver) on other glassware meaning a vessel will deliver a certain amount of liquid. Image File history File links Volumetric_flask. ... Fig. ...

Volumetric flasks typically come with a stopper or cap for capping the opening at the top of the neck. Such stoppers can be made of glass or plastic. When a glass stopper is used (see image at left), the opening at top of the neck has an outer (or female) tapered (conical) ground glass joint and the glass stopper has a matching tapered inner (or male) ground glass joint surface, but often only of stopper quality. Very small volumetric flasks (capacity of a milliliter or less) need a base to stand on so they will not tip over easily. The term stopper may refer to one of the following Stopper, a type of a knot at the end of the rope Stopper, a plug or a bung. ... A reflux set-up with conically-tapered ground glass joints connecting the Graham condenser with the vacuum adapter (top) and two-necked flask. ...

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Categories: Laboratory glassware | Volumetric instruments Laboratory equipment refers to the various tools and equipment used by scientists working in a laboratory. ... An agar plate streaked with microorganisms isolated from a deep-water sponge. ... A copper aspirator. ... Front loading autoclaves are common Stovetop autoclaves need to be monitored carefully, but have a very large capacity Multiple large autoclaves are used for processing substantial quantities of laboratory equipment prior to reuse, and infectious material prior to disposal. ... A bunsen burner with needle valve. ... A calorimeter is a device used for calorimetry, the science of measuring the heat of chemical reactions or physical changes as well as heat capacity. ... An electronic bacterial colony counter. ... A colorimeter is a device used to measure the absorbance of a specific solution. ... A laboratory tabletop centrifuge A centrifuge is a piece of equipment, generally driven by a motor, that puts an object in rotation around a fixed axis, applying force perpendicular to the axis. ... A common modern fume hood. ... In microbiology, an incubator is a device for controlling the temperature, humidity, and other conditions in which a microbiological culture is being grown. ... UV light desinfects the sterile laminar flow cabinet when not in use Laminar flow cabinet or laminar flow closet is a carefully enclosed bench designed to prevent contamination of semiconductor wafers, biological samples, or any particle sensitive device. ... A magnetic stirrer consists of a small bar magnet (or stir bar), which is normally wrapped in plastics like PTFE and a stand or plate containing a rotating magnet or stationary electomagnets creating a rotating magnetic field. ... A microscope (Greek: (micron) = small + (skopein) = to look at) is an instrument for viewing objects that are too small to be seen by the naked or unaided eye. ... A 96-well microtiter plate. ... Plate readers (also know as microplate readers) are laboratory instruments designed to detect biological, chemical or physical events in samples stored in microtiter plates. ... A Spectrophotometer In physics, spectrophotometry is the quantitative study of electromagnetic spectra. ... A stir bar (or flea) is a magnetic bar, used to stir a chemical reaction mixture or solution in a laboratory. ... A common mercury thermometer A thermometer is a device which measures temperature or temperature gradient, using a variety of different principles. ... A Mini-Vortexer with micro-centrifuge tube. ... Three static mixers: The top is an alternating spiral with each spiral offset by 90Â°; the second is the above in a delivery tube, such as for epoxy; the last is a larger metal mixer used to divide a flow into streams that intersect at 90Â°. - Static Mixers use the... Brown glass jars with some clear lab glassware in the background Laboratory glassware refers to a variety of equipment, traditionally made of glass, used for scientific experiments and other work in science, especially in chemistry and biology laboratories. ... A beaker is a simple container for liquids, very commonly used in laboratories. ... A large, thick-walled laboratory tube used for strongly heating substances with a Bunsen burner or other heat source. ... A BÃ¼chner funnel connected to a flask with a tube leading to a vacuum pump BÃ¼chner funnel is a piece of laboratory equipment used in suction filtration. ... A burette (also buret) is a vertical cylindrical piece of laboratory glassware with a volumetric graduation on its full length and a precision tap, or stopcock, on the bottom. ... A conical measure is a type of laboratory glassware which consists of a conical cup with a notch on the top to allow for the easy pouring of liquids. ... Crucibles used in Czochralski method A crucible is a cup-shaped piece of laboratory equipment used to contain chemical compounds when heating them to very high temperatures. ... A cuvette is a kind of laboratory glassware, usually a small square tube, sealed at one end, made of plastic, glass, or optical grade quartz and designed to hold samples for spectroscopic experiments. ... Erlenmeyer flasks from the Argonne National Laboratory glassblowing shop. ... Conical flask An Erlenmeyer flask (also known as a conical flask) is a widely used type of laboratory glassware which features a conical base with a cylindrical neck. ... Round-bottom flasks are types of flasks having spherical bottoms used as laboratory glassware, mostly for chemical or biochemical work. ... Florence flask A Florence flask (also known as a round bottom flask or a boiling flask) is a piece of laboratory glassware. ... A BÃ¼chner funnel connected to a flask with a tube leading to a vacuum pump A BÃ¼chner flask, also known as a vacuum flask, is a thick-walled erlenmeyer flask with a glass tube and hose barb protruding about an inch from its neck, connected to an aspirator. ... A retort. ... A gas syringe is a piece of laboratory glassware used to draw a volume of a gas from a beaker or other closed system, or measure the volume of gas given off in a reaction. ... Graduated cylinder. ... A selection of pipettes A pipette (also called a pipet or a pipettor) is a laboratory instrument used to transport a measured volume of liquid. ... Man looking at fungus inside of petri dishes A Petri dish is a shallow glass or plastic cylindrical dish that biologists use to culture microbes. ... Separating funnel A separating funnel or separation funnel or separatory funnel is a piece of equipment used in science to separate two immiscible liquids or solutions of different densities. ... A schematic representation of a Soxhlet extractor A Soxhlet extractor is a type of laboratory glassware invented in 1879 by Franz von Soxhlet. ... A test tube (Sometimes culture tube) is a kind of laboratory glassware, composed of a fingerlike length of glass tubing, open at the top, sometimes with a rounded lip at the top, and a rounded U shaped bottom. ... A thistle tube is a piece of laboratory glassware consisting mostly of a shaft of tube, with a reservoir and funnel-like section at the top. ... Caesium fluoride sample on a watch glass A watch glass is a circular, slightly concave piece of glass used in chemistry as a surface to evaporate a liquid, or as a cover for a beaker. ...

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