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Science Lab Equipment Identification Lab Florence Flask A Florence flask (also known as a round bottom flask or a boiling flask) is a piece of laboratory glassware It is a round or flat-bottom flask with a long neck It is designed for uniform heating and is produced in a number of different glass thicknesses to stand different types of use They are often made of borosilicate glass that has alkali to prevent cracks or defacing of the glass The flask is named after Florence, Italy Ring, Ring Stand, & Clamp Erlenmeyer Flask • An Erlenmeyer flask (also known as a conical flask) is a type of laboratory glassware which consists of an inverted conical base with a cylindrical neck The main advantages in an Erlenmeyer flask are that it is less likely to tip over than a Florence flask and the smaller neck slows evaporative loss better than a beaker It can also be swirled without fear of the contents spilling It is named after the German chemist Richard Erlenmeyer The conical flask's counterpart is the beaker However the main difference is that conical flasks may be stoppered using rubber bungs, so as the contents of the flask may be mixed or transported safely The flask is not usually used when heating substances vigorously, this task usually being left to the Florence flask Stopper • A stopper is a truncated conical piece of rubber or cork used to close off a glass tube, piece of laboratory glassware, a wine bottle or barrel and other containers with orifices A rubber stopper is sometimes called a rubber bung, and a cork stopper is called cork Ground glass stoppers are commonly used with laboratory glassware, mainly because of their nonreactivity Beaker • A beaker is a type of laboratory glassware which consists of a cylindrical cup with a notch on the top to allow for the pouring of liquids They are about as wide as they are tall This makes beakers very stable and easy to handle They may be made of plastic, glass, or Pyrex® Some beakers have graduated markings, or calibrations, to allow an easy rough measure of liquid volume As a means to make solutions, they are probably the most used piece of laboratory glassware Coupled with a good magnetic stirrer, they see frequent heavy use in a laboratory Like a test tube or a boiling tube, a beaker can be placed over a burning flame (such as a Bunsen burner) to be heated Test Tube • 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 They range in size from a few centimetres to over 20 centimetres in length and from a few millimetres to several centimetres in diameter They are designed to allow easy heating of samples, to be held in a flame, and often are made of expansionresistant glasses, such as Pyrex Tests tubes are often preferred above beakers when multiple small chemical or biological samples have to be handled and/or stored Test Tube Rack Used to store and hold test tubes in an upright position Test Tube Holder Used to hold test tubes, especially when heated or containing harmful chemicals Test Tube Brush Used to clean the insides of test tubes Microscope Slide & Cover Slip • A microscope slide is a thin sheet of glass used to hold objects for examination under a microscope A standard microscope slide (shown on the right) is 75 x 25 mm (3" X 1") and 1.2 mm thick A range of other sizes is available for various special purposes Since compound or high power microscopes have a very narrow region within which they focus, the object to be viewed ("specimen") is typically placed on the middle of the slide with another, much thinner square (or circle or rectangle) of glass placed over the specimen This smaller sheet of glass is called a cover slip or cover glass, and typically measures between 18 and 25 mm on a side The cover glass serves two purposes: (1) it protects the microscope's objective lens from contacting the specimen, and (2) it creates an even thickness (in wet mounts) for viewing Hand Lens/Magnifying Glass • A magnifying glass is a single convex lens which is used to produce a magnified image of an object The lens is usually mounted in a frame with a handle The magnifying glass is the simplest form of optical microscope A magnifying glass works by creating a magnified virtual image of an object behind the lens The distance between the lens and the object must be shorter than the focal length of the lens for this to occur A lens is a device for either concentrating or diverging light, usually formed from a piece of shaped glass Telescope The word "telescope" (from the Greek tele = 'far' and skopein = 'to look or see'; teleskopos = 'farseeing') usually refers to optical telescopes, but there are telescopes for most of the spectrum of electromagnetic radiation and for other signal types An optical telescope is an optical tool that gathers and focuses electromagnetic radiation Telescopes increase the apparent angular size of distant objects, as well as their apparent brightness Telescopes work by employing one or more curved optical elements - lenses or mirrors to gather light or other electromagnetic radiation and bring that light or radiation to a focus, where the image can be observed, photographed or studied