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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.〔Oxford English Dictionary 1989 edition〕 Most also have a small spout (or "beak") 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 & Common Uses== Standard or "low-form" beakers typically have a height about 1.4 times the diameter.〔British Standard 6523 (1984) ''Glass beakers for ginal experiments use''〕 The common low form with a spout was devised by John Joseph Griffin and is therefore sometimes called a Griffin beaker.〔A. I. Vogel (1974) ''Practical Organic Chemistry'' Third edition (Longman, London) page 46 ISBN 0-582-44245-1〕〔(Chemistry World August 2011 ) Classic kit: Griffin's Beaker〕 These are the most universal character and are used for various purposes - from preparing solutions and decanting supernatant fluids to holding waste fluids prior to disposal to performing simple reactions. In short, low form beakers are likely to be used in some way when performing just about any chemical experiment. "Tall-form" (B) beakers have a height about twice their diameter.〔 These are sometimes called Berzelius beakers and are mostly used for titration.〔 Flat beakers (C) are often called crystallizers because most are used to perform crystallization, but they are also often used as a vessel for use in hot-bath heating. These beakers usually do not have a flat scale. 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. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Beaker (glassware)」の詳細全文を読む スポンサード リンク
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