COMMON LAB EQUIPMENT USES AND VOCABULARY REVIEW Tools for Understanding Matter Alabama Science in Motion Updated Jan 2017 1 Which piece of lab equipment would be the best to crush a solid into powder? 2 Which piece of lab equipment would be the best to precisely deliver 5 mL of liquid? 3 COMMON LAB EQUIPMENT AND USES 4 Beaker Beakers are used to mix chemicals, dissolve solids into solutions, heat or cool solutions and measure liquid volume in mL. They have very poor accuracy and should only be used to estimate volumes. 5 Erlenmeyer Flask Like beakers, Erlenmeyer flasks can be used to mix, dissolve solids into solutions, and heat or cool solutions. Unlike beakers, Erlenmeyer flasks were developed for swirling solutions with minimum loss and they can be plugged with stoppers and used to catch vapor or condensed liquid. Their graduations are not very accurate. 6 Graduated Cylinder Graduated Cylinders are used to more accurately measure volumes of liquids in milliliters (mL). Measurement readings should be taken at eye level from the bottom of the meniscus, the concave curved surface formed at the top of the liquid. 7 Volumetric Flask A Volumetric Flask is used to accurately prepare solutions. A weighed amount of solid chemical is placed at the bottom, and the liquid solvent is added until the fill line is reached. The volumetric flask shown here is used to prepare a 250-mL solution at the fill line. 8 Pipet (Pipette) Pipets are used to measure or transfer liquids. Mohr pipets (shown) are graduated pipets used for precise measurement. A pipet pump (top) or a pipet bulb (bottom) is attached to the end of the pipet to help draw up and release liquid. 9 Micropipet (Micropipette) A micropipet is a precise method used to transfer small volumes of liquids in chemical, biological and medical laboratories. Pressin g on a plunger button at the top of the micropipet will pull the liquid in, and a second press will dispense it. The tips are disposable. 10 Dropper A dropper is a glass tube with a hollow rubber bulb at one end and a small opening at the other, for drawing in a liquid and expelling it in drops. 11 Buret (Burette) A Buret is an extremely accurate device with a stopcock at the bottom used to measure volumes of reagents. Burets are often used to determine the concentration of a solution by dispensing a solution with a known concentration in a process known as titration. (Shown with Ring Stand and Double Buret Clamp) 12 Ring Stand A ring stand is a metal stand consisti ng of a long upright rod attached to a heavy rectangular base that is used with rings and clamps for supporting laboratory apparatus. 13 Double Buret Clamp A double buret clamp is attached to a ring stand to hold up to two burets. 14 Support Ring An iron support ring is mounted to a ring stand and is used in chemistry labs to stabilize flasks, beakers and other glassware and support them over the work area. 15 Test Tube Clamp A test tube clamp is attached to a ring stand and is used to hold test tubes and other cylindrical pieces of equipment such as burets, gas collection tubes, data-collection probes, etc. 16 Test Tube Rack Test tube racks are used for holding test tubes upright when they contain chemicals, and also hold test tubes upside down to dry. They can be made of wood, metal, or plastic. 17 Test Tube Test tubes are narrow glass cylinders, closed at one end, that are used for mixing, heating, and storing small quantities of chemicals. They are usually made of a type of glass (such as Pyrex®) that can withstand high temperatures. Test tubes come in many different sizes. 18 Test Tube Brush A test tube brush is used for cleaning test tubes and narrow mouth laboratory glassware, such as beakers and flasks. 19 Funnel Funnels are used to pour liquids into narrowmouth containers such as flasks and bottles. Buchner funnels (pictured right) are special two-piece funnels for filtering mixtures through filter paper into a filtering flask. 20 Mortar and Pestle A mortar and pestle is a device used since ancient times to prepare ingredients or substances by crushing and grinding them into a fine paste or powder. The mortar is a bowl, typically made of hard wood, ceramic or stone. 21 Crucible and Cover A crucible is used to heat solid chemicals over a burner at high temperatures. They are made from heatresistant ceramics to prevent breakage. A cover is used to contain any smoke particles. 22 Clay Triangle A clay triangle is used to hold a crucible while it is being heated. 23 Watch Glass Watch glasses can be used to cover beakers, evaporate water from solutions, weigh out solid chemicals, or observe samples under a stereo microscope. 24 Evaporating Dish An evaporating dish is used to separate water and solids from a solution by allowing the water to evaporate off into the air. This is usually done by heating the evaporating dish over a burner or hot plate. 25 Bunsen Burner A Bunsen burner is attached to a gas line and lit to provide heat for performing experiments. 26 Hot Plate Hot plates are generally used to heat glassware or its contents. Some hot plates also contain a magnetic stirrer, allowing the heated liquid to be stirred automatically. 27 Hot Mitt A hot mitt is used to grip and transfer hot glassware. 28 Wire Gauze A Wire gauze is a sheet of thin metal that has net-like crosses or a wire mesh. The purpose of wire gauze is to be placed on the support ring that is attached to the ring stand between the Bunsen burner and the beakers to diffuse the heat and to support the beakers or other glassware or flasks during heating. 29 Test Tube Holder A test tube holder is used to hold and transport hot test tubes. 30 Crucible Tongs Crucible tongs are used to hold and transport hot crucibles. 31 Beaker Tongs Beaker tongs are used to hold and transport hot beakers. They have a plastic coating which should be kept away from heat/flames. 32 Weigh Boat A weigh boat is an open container, often disposable, used for weighin g samples. 33 Scoopula (Metal Scoop) A scoopula, or metal scoop, is an instrument used to transfer solids from one place to another. 34 Top-Loading Balance Electronic balances are used to measure the mass of substances accurately. The balance is calibrated so that the amount of resistance placed on the balance pan corresponds to a given mass value (which is then displayed on the LCD readout). Do not place chemicals directly on the balance pan. Use a weigh boat. Top-Loading balances can usually mass substances to the nearest gram, tenth of a gram or hundredth of a 35 Analytical Balance Analytical balances are much more precise and cost much more than toploading balances. They are sensitive to vibrations (be still and do not lean on the lab bench) and to air flow (close the glass doors). Most of the analytical balances provided by AL Science in Motion can mass substances to 4 decimal places (0.0001g). 36 Well Plate The well plate is a flat plate tha t looks like a tray with multiple well s that are used as small test tubes. 37 Forceps Forceps (tweezers) are a handheld, hinged instrument used for grasping and holding objects. Forceps are used when fingers are too large to grasp small objects or when many objects need to be held at one time while the hands are used to perform a task. 38 Thermometer A thermometer is used to measure temperature in degrees Celsius or Fahrenheit. Most sold today are filled with alcohol instead of mercury. 39 Ruler A metric ruler, also called a rule or, especially in the printing industry, a line gauge, is a measuring instrument used in technical drawing, geometry, engineering, printing and construction to rule straight lines and calculate distances in centimeters and inches. 40 Stirring Rod Stirring rods are used to stir mixtures and facilitate the pouring of liquids. Stirring rods are usually made of glass. 41 Wash Bottle A wash bottle is used to store and dispense distilled or deionized water. 42 Goggles Goggles are to be worn to protect your eyes when handling chemicals or glass. Make sure that there is a good seal at the forehead to prevent chemical splashes from running down into your eyes. 43 Apron An apron is personal protection equipment (PPE) worn to protect clothing from chemical spills. 44 VOCABULARY 45 MATTER • Matter is anything that has mass and takes up space (volume). • Density is the amount of matter in a given volume. • Density = Mass / Volume , units: g/mL or g/cm3 • Matter is either a mixture or it is a pure substance. • Mixtures can be classified into two categories – • Homogeneous mixtures (the same throughout; solutions) • Heterogeneous mixtures (different throughout). • Pure substances can be classified into two categories – • Elements (made of only one type of atom) • Compounds (made of two or more elements chemically combined) 46 PHYSICAL PROPERTIES OF MATTER • Physical properties can be observed or measured without changing the composition of matter. • Physical properties are used to observe and describe matter. • Some physical properties depend on the amount of the substance being used and some do not. • Examples of Physical Properties • appearance • texture • color • odor • melting & boiling points • density • solubility • and many others. 47 CHEMICAL PROPERTIES OF MATTER • Chemical properties are any of the properties of matter that may only be observed and measured by performing a chemical change or chemical reaction. • Chemical properties cannot be determined by touching or viewing a sample; the structure of the sample must be altered for the chemical properties to become apparent. • Examples of Chemical Properties • reactivity with other chemicals • toxicity • flammability • chemical stability • ability to rust 48 ACCURACY & PRECISION • Accuracy is defined as coming close to a true or desired value, like the center of a bullseye. • Precision reflects how well a series of measurements agree with each other, whether or not any of them are close to the true value. For the values to also be precise, they would need to be very close to each other (whether or not they hit the mark). • Precision can often be adjusted using calibration to yield values that are both accurate and precise. • Scientists often report percent error of a measurement, which expresses how far a measured value is from the true value. Michael Betts, Getty Images 49 MEASUREMENT • A ruler is used to measure distance/length. •1 m = 100 cm = 1000 mm •1 km = 1000 m •1 in = 2.54 cm • A balance is used to measure mass in grams. Steps for using an electronic balance: 1.Place a weigh boat on the pan (close all doors if analytical balance) 2.Press the zero/tare button & wait until digital units are displayed 3.Place the object to be massed in the weigh boat (close all doors if analytical balance) & wait until digital units are displayed 1.Record the mass using all decimal place values shown (do not 50 MORE EQUIPMENT (not as common in some high school chemistry labs) 51 Three-Prong Clamp A three-prong clamp is attached to a ring stand and is used to secure lab equipment. 52 Graduated Pipet A graduated pipet is made of disposable plastic with graduated marking on it so that a precise volume of liquid can be transferred. 53 Thin Stem Pipet A thin stem pipet is made of disposable plastic and is used for transferring small amounts of liquid, usually one drop at a time. 54 Stopwatch A stopwatch is a watch that can be started and stopped for exact timing. It is used in the science lab to time how long something takes to complete such as a chemical reaction or the motion of a moving object. 55 Centrifuge A centrifuge is a machine with a rapidly rotating container that applies centrifugal force to its contents, typically to separate fluids of different densities or liquids from solids. 56 Petri Dish Petri dishes are used to hold specimens for observation and to grow cultures. 57 Triangular File A triangular file is used in the chemistry lab to score glass tubing to create clean breaks in the glass. 58