BBeaker (glassware)

7 Maret 2010 pukul 07:53 | Ditulis dalam Uncategorized | Tinggalkan komentar
A beaker is a simple container for stirring, mixing and heating liquids commonly used in many laboratories. Beakers are generally cylindrical in shape, with a flat bottom and a lip for pouring.[1] Many also have a small spout to aid pouring as shown in the picture. Beakers are available in a wide range of sizes, from one millilitre up to several litres.

Structure

Standard or “Low-form” beakers typically have a height about 1.4 times the diameter.[2] The common low form with a spout has been called the Griffin form.[3] “Tall form” beakers have a height about twice the diameter.[2] These are sometimes called Berzelius beakers.

A beaker is distinguished from a flask by having sides which are straight rather than sloping. The exception to this definition is a slightly conical sided beaker called a Phillips beaker.

Materials

Beakers are commonly made of glass (today usually borosilicate glass[2]), but can also be in metal (such as stainless steel or aluminium) or certain plastics, (notably polythene, polypropylene, PTFE). A common use for polypropylene beakers is gamma spectral analysis of liquid and solid samples.

Shape

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 would be a more appropriate instrument for such a task), but rather an estimation.

The presence of a lip 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.

Tinggalkan sebuah Komentar »

RSS feed for comments on this post. TrackBack URI

Tinggalkan Balasan

Isikan data di bawah atau klik salah satu ikon untuk log in:

Logo WordPress.com

You are commenting using your WordPress.com account. Logout / Ubah )

Gambar Twitter

You are commenting using your Twitter account. Logout / Ubah )

Foto Facebook

You are commenting using your Facebook account. Logout / Ubah )

Foto Google+

You are commenting using your Google+ account. Logout / Ubah )

Connecting to %s

Buat situs web atau blog gratis di WordPress.com.
Entries dan komentar feeds.

%d blogger menyukai ini: