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Public archive edition · Attributed source reporting with original dates · AI drafts are excluded

411 REFERENCE · Wikibooks

Science: A Field Of Wonder/About The Laboratory

Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.

Basic Laboratory Tools How do you make scientific investigations? To be reliable and accurate, scientific investigations need data to help prove or disprove a hypotheses. In order to gather appropriate data, the following laboratory equipment and their uses are presented below. +Heating InstrumentsLaboratory EquipmentDescription/UseIllustrationBunsen burnerA source of heat when nonluminuous flame is needed for experiment workhttps://store.schoolspecialty.com/OA_HTML/xxssi_ibeGetWCCImage.jsp?docName=F1635011&Rendition=LargetripodA stand with three legs used for supporting the wire gauze and container with liquid to be heatedhttps://cdn11.bigcommerce.com/s-ufhcuzfxw9/images/stencil/original/products/13266/14343/CE-TRIPOD5__70828.1503517910.jpg?c=2&imbypass=oniron standThis is used to support the setup for the heating process.https://marslabph.com/wp-content/uploads/2016/12/ironstand.jpgalcohol lampIt is a source of heat in the laboratory.https://www.3riversarchery.com/mm5/graphics/00000001/5376_341x500.jpg +ContainersLaboratory EquipmentDescription/UseIllustrationbeakerThis is a deep, wide-mouthed, cylindrical vessel with a pouring lip. It is used for measuring large quantities of liquid; it also serves as a container of boiling liquid mixture.https://pim-resources.coleparmer.com/item/l/cole-parmer-3450352-griffin-low-form-beaker-glass-250-ml-12-pk-3450352.jpgErlenmeyer flaskThis is a flat-bottomed flask that has a wide bottom and a narrow mouth or opening.https://www.labdepotinc.com/admin/uploads/ac070527l_medium.jpgtest tubeThis is used to contain small amounts of solution for boiling or for storage.https://5.imimg.com/data5/AU/DY/MY-957949/laboratory-glass-test-tubes-500x500.jpgFlorence flaskThis is a round-bottomed flask used as a container for boiling liquid solution.https://cdn11.bigcommerce.com/s-ufhcuzfxw9/images/stencil/original/products/13038/16907/CE-FLOR500__65671.1522703167.jpg?c=2&imbypass=on +Measuring Device (Mass)Laboratory EquipmentDescription/UseIllustrationplatform balanceThis is used for weighing materials accurately in various containers or vessels.https://www.mrmprecision.ca/wp-content/uploads/2017/07/Harvard-Trip%C2%AE.jpgtop loading balanceThis is used for weighing materials electronicallyhttps://www.dataweigh.com/media/11904/entris-top-loader.png +Measuring Device (Liquid Volume)Laboratory EquipmentDescription/UseIllustrationgraduated cylinderThis is used for measuring the volume of liquidshttps://www.brandtech.com/wp-content/uploads/glass_cylinder_new.jpgpipetteThis is used for measuring a small volume of liquid direct from the reagent bottlehttps://cdn7.bigcommerce.com/s-ufhcuzfxw9/images/stencil/500x659/products/12140/15341/CE-PIPE05A__25042.1503517926.jpg?c=2dropperThis is used in transferring and measuring small amount of liquidhttps://www.aromatools.com/media/catalog/product/cache/1/image/1800x/6beb0238d6dd6cb8069692f5b293db57/9/1/9157f.jpg +Measuring Device (Length)Laboratory EquipmentDescription/UseIllustrationtape measureA tape or thin flexible metal, marked at intervals for measuring lengthhttps://s.hswstatic.com/gif/tape-measure-1.jpgmeterstickA one-meter long ruler that is usually marked off in centimeters and milimetershttps://cdn.krafttool.com/images/product/medium/SLM39.JPG +Measuring Device (Temperature)Laboratory EquipmentDescription/UseIllustrationthermometerThis is used for measuring temperaturehttps://nelsonjameson.com/secure/images/products/1011578.jpg +Measuring Device (Time)Laboratory EquipmentDescription/UseIllustrationstopwatchThis is a special watch with buttons that start and stop. It is used to measure the amount of time to do an activity.https://sc02.alicdn.com/kf/HTB1rXz8QVXXXXadXpXXq6xXFXXXu/Laboratory-professional-Stopwatch-countdown-Timer.jpg_350x350.jpg +Laboratory EquipmentDescription/UseIllustrationtest tube rackA framework of wooden or metal bars for supporting the test tubes when not in use or while waiting for the reaction of reagents to take place.https://cdn11.bigcommerce.com/s-ufhcuzfxw9/images/stencil/original/products/11734/16286/ce-ttrack4__89156.1503517951.jpg?c=2&imbypass=onwatch glassA crystal used for observing a small amount of sample that is undergoing reaction.http://www.capitolscientific.com/core/media/media.nl?id=59756&c=1250437&h=4ccdc350132ab41e5038test tube holderA strong metal wire used to hold test tubes.https://4.imimg.com/data4/BV/IF/MY-16630388/test-tube-holder-500x500.jpgmortar and pestleThis set is used for pounding and grinding solid substances into powder form.https://slimages.macysassets.com/is/image/MCY/products/2/optimized/2725842_fpx.tif?op_sharpen=1&wid=500&hei=613&fit=fit,1&$filtersm$funnelThis is used for pouring liquids or powders into containers with small opening and for holding the filter paper during filtration.https://pim-resources.coleparmer.com/item/l/pyrex-6140-65-6140-glass-funnel-65-mm-top-dia-62-ml-6-pk-3456051.jpgwire gauzeThis is used to regulate the heat of the glame when used in heating.https://cdn11.bigcommerce.com/s-ufhcuzfxw9/images/stencil/500x659/products/13125/14331/CE-GAUZE4__94252.1503517909.jpg?c=2clay triangleThis is used to support the crucible for direct heating.https://cdn11.bigcommerce.com/s-ufhcuzfxw9/images/stencil/original/products/11320/13772/CE-TRIAN25__84696.1503517900.jpg?c=2&imbypass=onevaporating dishA porcelain dish in which a solution may be evaporated to leave the dissolved substance as a residuehttps://cdn11.bigcommerce.com/s-ufhcuzfxw9/images/stencil/original/products/12072/14358/CE-EVAPDSH__23331.1503517910.jpg?c=2&imbypass=on Safety Devices Safety devices are used to protect yourself when working inside the laboratoryroom. Common examples of safety devices are as follows: Laboratory Gown or Apron A laboratory gown is worn to protect the skin and clothing from spills. Safety Goggles These are worn in the laboratory to protect the eyes from harmful and toxic substances. Gloves These are used to protect the hands from contact with harmful substances, broken glass, and hot objects. Safety Symbols The following safety symbols will appear in the laboratory experiments to emphasize additional important areas of caution. Learn what they represent so you can take the appropriate precautionary measures. Electric Shock This indicates that electrical outlets should not be touched when hands are wet. Disposal This means that used chemicals must be properly disposed of in specific containers. Poison This means that the substance is harmful, deadly, and should not be touched, tasted, or inhaled. Common Laboratory techniques Heating a Substance in a Test Tube When you are heating a test tube always use a test tube holder. always hold the test tube at an angle like in figure shown below never point a test tube of liquid being heated to yourself or to your classmates. distribute the heat at the bottom of the test tube by passing the sides of the test tube up and down along the flame. Measuring Volume The volume of a liquid is measured by using a graduated cylinder. A graduated cylinder is marked in milliliters (mL). It measures small amounts like 10mL or large amounts like 100mL. In reading the volume of liquid in a graduated cylinder, place the setup on a flat surface. At eye level, read the lower meniscus. meniscus - the curve of the surface of the liquid Laboratory Safety Measures Safety and environmental consciousness is vital in doing laboratory activities. Always consider your own, your co-workers, and the environment's safety. Read the laboratory instructions of the experiment carefully before you start working on the experiment. Listen for further instructions from the teacher. Regard all waste disposals as a potential safety and environmental risk. Dispose of solid and liquid wastes properly. Ask your teacher how. Wear appropriate protective apparel such as gloves, laboratory gowns or aprons, and safety goggles. Take care of all equipment and apparatus. Clean them after use. Know all emergency and fire procedures. Become familiar with safety signs and symbols. Never taste a chemical or solution unless told to do so. Do not eat or drink in the laboratory. Report immediately any breakage of glassware or equipment to the teacher or laboratory assistant for proper disposal. Do not touch electrical outlets and gas cocks if not needed in the experiment. Never work inside the laboratory room unless supervised by the teacher or the laboratory staff.