Laboratory flask

Erlenmeyer flasks from the Argonne National Laboratory glassblowing shop.

Laboratory flasks are vessels (containers) which 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 stopper 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.

Legal issues

Like many other common pieces of glassware, Erlenmeyer flasks could potentially be used in the production of drugs. In an effort to restrict such production, some U.S. states (including Texas) have made possession of common flasks illegal in schools without permit, including Erlenmeyer flasks, as well as chemicals identified as common starting materials.[1]

See also

References

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

External links

Media related to Laboratory flasks at Wikimedia Commons

This article is issued from Wikipedia - version of the Tuesday, January 13, 2015. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.