Erlenmeyer flask

Conical flask used in a Titration setup

Conical flask

An Erlenmeyer flask (also known as a conical flask) is a widely used type of laboratory glassware which consists of an inverted conical base with a cylindrical neck. They usually contain some graduation marks to indicate the aproximate value of their contents.
It is named after the German chemist Richard Erlenmeyer, who created it in 1861.

The conical flask's counterpart is the beaker. However the main difference is its narrow neck. The main advantages are that it allows them to be stoppered using rubber bungs or hydrophobic cotton, stirring or swirling the contents of the flask frequently during an experiment (as is required in titration) without fear of the contents spilling, transporting them safely, or using them to deal with violent reactions. The smaller neck also slows evaporative loss better than a beaker; and, contrary to the Florence flask, is unlikely to tip over.
The flask is used to heat substances, yet not vigorously; the latter task usually being left to the Florence flask. Erlenmeyer flasks are also used for titration and in microbiology for the preparation of Microbial cultures.

As any piece of laboratory glassware, there is a specific method to use an Erlenmeyer flask correctly. To keep the flask firmly planted, a 'C' shaped lead or iron weight may be placed over the outside.
When heating, it is usually placed on a ring held to a ring stand by means of a ring clamp or similar. The ring keeps it over a Bunsen burner so that it's heated by the burner's flame. When set up this way, a wire gauze mesh or pad is placed between the ring and the flask. An alternative way to set up the aparatus is to clamp the flask directly to the ring stand by means of holding it with a test tube clamp around the flask's neck.

Erlenmeyer flasks are very important in the process of culturing bacteria.