DOCSLIB.ORG

Lab Policies and Information

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Lab Policies and Information CH 105/106 LAB POLICIES AND INFORMATION Contents Introduction to Chemistry 105/106 Laboratory 2 About Cooperative Learning 3 Safety Rules 4 Laboratory Etiquette 6 NFPA Hazard Codes, Waste Disposal and MSDS 7 Getting Started 8 Portfolio Assignment 9 Laboratory Equipment 10 1 INTRODUCTION TO CHEMISTRY 105/106 LABORATORIES The Chemistry 105/106 Course Sequence has as a required component the laboratory portion of the course. The laboratories are designed to enhance your experience of chemistry, by providing “hands-on” experience in a variety of activities that are used by real scientists. The laboratory portion of the course may explore ideas that are the same/similar to those discussed in the classroom, and will often go beyond the classroom topics. This is designed to broaden your experience of chemistry. Chemists do not limit themselves to what is found in one textbook or classroom, so you are provided opportunities to explore a variety of topics in your own experimental work. You will find several types of experimental approaches in this laboratory course. Some will have a traditional format, where instructions or procedures are provided for you. Some will have an open-ended, cooperative learning format that is probably different than most science laboratories you may have experienced. Cooperative Learning Laboratories are discussed on page 3. As an accompaniment to your laboratory work, you will also be assembling a portfolio, maintaining a laboratory notebook, and preparing oral reports. You may be working individually, in pairs, or in groups for different experiments or different sections of an experiment. This variety of activities is designed to provide opportunities to practice the different skills you will need to learn about the different subjects with which you will be confronted during your college career, and your life. A syllabus will be given to you during the first lab period at which time your lab instructor will explain the details and answer any questions you may have. 2 COOPERATIVE CHEMISTRY LABORATORIES: Welcome to the Cooperative Chemistry Laboratories! Your experience in these laboratories will probably be different from the types of science labs you have previously seen. Instead of a set of specific instructions, you will find an open-ended research problem. The broader questions and problems posed in these research problems will require several weeks of strategy planning, laboratory work, and some information research on different topics. Thus, instead of performing a series of 11 or 12 experiments that are each completed in an afternoon, you might spend several weeks on one experiment, and complete two, three or four each semester. Another aspect of Cooperative Chemistry Laboratories involves becoming a member of a group or team. You will join three or four other students in small group to work on the assigned, open-ended projects. You and your group members will bring different knowledge and experiences to the group, which will enhance your ability to tackle more complex problems. Real scientists have complex, open-ended research projects, not a simple recipe. The Cooperative Chemistry Laboratories are thus designed to provide you with a laboratory experience that is realistic, more like the “real world”. You will find the resources and guidance to devise your own strategic plan for each experiment. You will find information and assistance for performing experiments, and gathering and interpreting your results. You will NOT be given a simple “right” answer. There may not be a simple “right” answer. This means that you will be graded on how you plan your experiments, evaluate your results, and present your report. The lab is not designed to coordinate with the lecture course on specific topics. However, the topics discussed in the laboratory will reinforce the lecture topics to some extent. There will also be new topics that may later be applicable to the lecture portion of the course. One important skill that we will be concerned with teaching you is, how to think your way through problems. This is a skill that can be used in any field of study, and is valuable throughout life. 3 SAFETY RULES 1. Wear your goggles. Wear approved eye protection at all times while in the laboratory and in any area where chemicals are stored or handled. Eye protection should protect against impact and chemical splashes. Goggles, which conform to the ANSI Z-87.1, 1989 standard, are required. Prescription glasses and sunglasses are not acceptable forms of eye protection. If you purchase goggles make sure that they have the ANSI Z-87.1, 1989 imprint on them and that they are designated as chemical splash goggles. Under no circumstances should you wear contact lenses in the laboratory, even under goggles. Chemical vapors may dissolve in the liquids covering the eye and concentrate behind the lenses. "Soft" contact lenses are especially dangerous as chemicals can dissolve in the lenses themselves and be released over a period of several hours. The laboratory has an eyewash station for your use. In the event that a chemical splashes near your eyes, use the station before the material runs behind your safety glasses and into your eyes. You should irrigate your eyes for at least five minutes and notify your laboratory instructor. 2. Don't ingest anything. Eating, drinking and smoking are prohibited in the laboratory at all times. 3. Dress like a chemist. Wear clothing in the laboratory that will provide maximum body coverage. Shorts, mini-skirts, etc. are completely inappropriate. Your clothing should come down to your ankles. Wearing open-toed shoes and sandals is also not allowed in lab. It is advisable to wear old clothes in the laboratory in case of spills. You might also want to keep a pair of sweat pants in your drawer. Long hair should be securely tied back to avoid the risk of setting it on fire or getting contaminated with chemicals. If large amounts of chemicals are spilled on your body, remove the contaminated clothing and use the safety shower located in your laboratory. Stand under the shower for at least five minutes, and make sure that your laboratory instructor is aware of the problem. 4. Don't touch any chemicals. Never taste or touch any chemical. Many chemicals are absorbed through the skin. Wash off all chemicals with large quantities of running water. If directed to smell a vapor, gently waft the vapors towards your nose. Do not smell the source of the vapor directly. 4 5. Use the hood. Perform any reactions involving toxic, irritating or otherwise dangerous chemicals or unpleasant odors in the hood. Each student should have access to a hood. 6. Know what to do if there is an accident. In case of fire or an accident, call the instructor at once. Note the location of the fire extinguishers, safety showers and safety blankets as soon as you enter the laboratory so that you may use them if needed. a) Wet towels can be used to smother small fires. b) If a person's clothing catches fire, pull out the fire blanket, and roll the person up in it to smother the fire. c) In case of a chemical spill on your body or clothes, stand under the safety shower, and flood the affect area with water. Remove contaminated clothing to prevent further reaction with the skin. NOTIFY YOUR INSTRUCTOR IN CASE OF ANY ACCIDENT, NO MATTER HOW SLIGHT. 7. Work safely. Do not point a test tube at anyone while you are heating it; it may erupt. 8. Beware of glass. It is breakable. When inserting glass tubing or thermometers into stoppers, lubricate both the tubing and the hole in the stopper with water. Wrap the tubing in a towel, grasp it as close to the end being inserted as possible, and push gently, using a twisting motion. 9. Assume you are the only safe worker in the lab. Work defensively. Do not assume that every one else is as safe a worker as you are. Wear your goggles even when you are not working. Be alert for others' mistakes. 10. Do not wear headphones in the lab. Anything that interferes with your ability to hear what is going on in lab is a potential hazard. 11. If you are or become pregnant, notify your TA at the next lab so safety issues may be addressed. 5 Basic Laboratory Etiquette Many other students use the equipment you use in this laboratory. Please leave the equipment and all workspaces, as you would wish to find them. 1. If you find a piece of equipment that is not in good working order, notify your TA immediately so that a work order for its repair can be filled out. 2. After you have finished work in the lab, clean off your work area so that it is in good shape for the next person in lab. Each group needs to bring a roll of paper towels and some liquid soap to keep in a lab drawer for cleaning purposes. 3. When obtaining reagents, do not take the reagent dispenser to your desk. 4. If you take more reagent than you need, do not put the excess back into the bottle. It may be contaminated at this stage. Treat the extra as waste and dispose of it accordingly. 5. You will be given instructions on how to dispose of waste chemicals on the basis of their toxicity. Do not put anything down the sink unless you are explicitly told to dispose of it this way. Most waste will be placed in labeled containers. 6. When weighing any material on the balances, do not weigh directly onto the balance pan. Weigh your material on a piece of weighing paper, or into a beaker or other container.
Load more

Recommended publications
  • Performance Validation of the Microbiologique Microfilm Test
    MAI ET AL.: JOURNAL OF AOAC INTERNATIONAL VOL. 101, NO. X, 2018 1 FOOD BIOLOGICAL CONTAMINANTS Performance Validation of the Microbiologique MicrofilmTM Test System for AOAC Research Institute Performance Tested Method SMCertification AOAC Performance Tested Method SM 051702 Abstract ANNA SHAPOVALOVA and HARISH K. JANAGAMA Molecular Epidemiology, Inc., 15300 Bothell Way NE, The Microfilm™ Test System is intended for quantitative Lake Forest Park, WA 98155 microbiology and consists of three types of Microfilms for aerobic LONG VUONG and ALEX FRIEDRICH plate count (Microfilm APC), total coliform and Escherichia coli IEH Laboratories and Consulting Group, Inc., 15300 Bothell count (Microfilm TCEc), and yeast and mold count (Microfilm Way NE, Lake Forest Park, WA 98155 YMC). This study evaluated the performance of the Microfilm DYLAN JOHNSON Test System against International Organization for Standardization Molecular Epidemiology, Inc., 15300 Bothell Way NE, (ISO) methods on 20 food matrixes and 2 environmental surfaces. Lake Forest Park, WA 98155 Ruggedness, robustness, and stability were also determined, LOURDES M. NADALA while inclusivity and exclusivity studies were performed on Molecular Epidemiology, Inc., 15300 Bothell Way N.E., Microfilm TCEc and YMC. An independent laboratory evaluated Lake Forest Park, WA 98155; Microbiologique, the performance on four food matrixes and one environmental Inc., 8215 Lake City Way NE, Seattle, WA 98115 surface. No significant differences and high correlation coefficients VAN NGUYEN were observed between the Microfilm Test System and the Microbiologique, Inc., 8215 Lake City Way NE, Seattle, corresponding ISO methods (ISO 4833-1:2013 for APC, ISO WA 98115 4832:2006 for total coliform count, ISO 16649-2: 2001 for E.
    [Show full text]
  • Flinn Scientific 2019 Purchase Guide a Quick and Easy Checklist of Science Essentials
    Flinn Scientific 2019 Purchase Guide A Quick and Easy Checklist of Science Essentials Use this Purchase Guide as a handy tool for: • Taking Inventory • Order Preparation • Budget Management • Future Planning See your Flinn Scientific Catalog/Reference Manual SCIENTIFIC or visit www.flinnsci.com for product details. It’s Easy to Order Tom Trapp from Flinn Scientific! National Account Development Consultant [email protected] www.flinnsci.com/tom-trapp/sa1001 Online 402-960-5578 (mobile) www.flinnsci.com Offering personal assistance to help meet your science curriculum, supply, and lab safety needs. Email [email protected] Quality Products, Fast Delivery, Fax and Low Prices Guaranteed 1-866-452-1436 (toll free) Mail Flinn Scientific, Inc. P.O. Box 219 Batavia, IL 60510-0219 Phone 1-800-452-1261 7:30 am to 5:00 pm CT Monday through Friday Our Guarantee Flinn Scientific, Inc. guarantees that no sale is complete unless the customer is satisfied. Every item we furnish will either conform to the catalog specification, or we will ask your permission, prior to shipment, to ship an alternative product. If you find a lower published nationally advertised catalog price for an identical item, Flinn will “meet or beat” that price. Use this purchase guide containing popular product recommendations ©2019 Flinn Scientific, Inc. All Rights Reserved. to prepare your order, take inventory, and manage your budget. 1 www.flinnsci.com Flinn Scientific 2019 Purchase Guide 1 Item Rec. Item Rec. Product / Item Name Qty 2019 Price Total Product / Item Name Qty 2019 Price Total No. Qty No. Qty Safety & Personal Protection Equipment Aspirator, Water, Polypropylene AP1203 1 $ 19.30 $ - Apron, rubberized, 27" W X 36" L AP7125 30 $ 15.00 $ - Autoclave, Electric, Portable AP1004 1 $ 865.20 $ - Apron, plastic, 30" W x 36" L AP7120 30 $ 7.25 $ - ♦ Balance, Flinn Triple Beam OB2181 $ 115.00 $ - Gloves, Butyl rubber for conc.
    [Show full text]
  • Bunsen Burner Safety
    Proper Use of a Bunsen Burner If using a Bunsen burner in a biological safety cabinet, see: http://research.wayne.edu/oehs/pdf/gas-in-bsc.pdf Prior to Lighting Bunsen Burner: • Know the location of the laboratory’s main gas shut off valve and fire extinguisher. • Place the Bunsen burner away from any overhead shelving, equipment, or light fixtures by at least 12 inches. • Remove all papers, notebooks, combustible materials, and excess chemicals from the area. • Tie-back any long hair, dangling jewelry, or loose clothing. • Use correct tubing (butyl rubber hose). Inspect hose for cracks, holes, pinch points, or any defect and replace if necessary. Ensure that the hose fits securely on the gas valve and the burner. • Notify others in the lab that the burner will be in use. Lighting Bunsen Burner: • Before turning on gas, have a sparker/lighter with extended nozzle to ignite burner. Never use matches. • Check connections to burner and desk outlet valve. • Close needle valve and collar. • Open gas valve fully. • Open needle valve 1/2 turn. • Use the spark/lighter to light the flame. • Adjust flame by turning the collar to regulate air flow and produce an appropriate flame for the experiment (typically a medium blue flame). During Use: • Never leave a lighted burner unattended. Drafts (including those created by a hood) may extinguish the flame, but the gas will still be on. This could result in an explosion. • Never face the vessel (test tube, beaker, etc.) being used to heat a material toward yourself or others near the burner. In some experiments, a hot plate may be used in place of the Bunsen burner.
    [Show full text]
  • SF#11086 Sterilization and Aseptic Technique
    Publication No. 11086 Sterilization and Aseptic Technique Introduction Microbiology lab activities are common in middle school and high school life science courses. Learning basic microbiology lab techniques and procedures is interesting and relevant to most students—many of them, after all, have had at least one throat culture or other microbiology lab test in their lives. The requirements for safe microbiological work in the classroom include the knowledge and practice of aseptic technique and sterilization procedures. Standard Microbiology Practices The federal government has outlined general safety standards for microbiological work in their publication Biosafety in Microbiological and Biomedical Laboratories. Biosafety Level I (BSL 1) practices described in this book are appropriate for secondary educational teaching laboratories. BSL 1 work involves using strains of viable, nonpathogenic microorganisms that are known not to cause disease in healthy adult humans and are thus of minimal potential hazard to students, teachers or the environ- ment. The level of containment in BSL 1 relies on standard microbiological practices in laboratory settings. Students and lab per- sonnel should receive specific training in the procedures conducted in the laboratory. Standard microbiological practices include: • Wash hands thoroughly with soap and water before and after handling viable materials, after performing microbiological transfers and observations or working with potentially hazardous materials, and before leaving the laboratory. • Eating, drinking, smoking, handling of contact lenses, applying cosmetics, and storing food for human use are not permit- ted in laboratory work areas. • Pipetting by mouth is prohibited—use only mechanical pipetting devices. • There should be policies and procedures for safe disposal of sharps, including broken glassware.
    [Show full text]
  • High School Chemistry
    RECOMMENDED MINIMUM CORE INVENTORY TO SUPPORT STANDARDS-BASED INSTRUCTION HIGH SCHOOL GRADES SCIENCES High School Chemistry Quantity per Quantity per lab classroom/ Description group adjacent work area SAFETY EQUIPMENT 2 Acid storage cabinet (one reserved exclusively for nitric acid) 1 Chemical spill kit 1 Chemical storage reference book 5 Chemical waste containers (Categories: corrosives, flammables, oxidizers, air/water reactive, toxic) 1 Emergency shower 1 Eye wash station 1 Fire blanket 1 Fire extinguisher 1 First aid kit 1 Flammables cabinet 1 Fume hood 1/student Goggles 1 Goggles sanitizer (holds 36 pairs of goggles) 1/student Lab aprons COMPUTER ASSISTED LEARNING 1 Television or digital projector 1 VGA Adapters for various digital devices EQUIPMENT/SUPPLIES 1 box Aluminum foil 100 Assorted rubber stoppers 1 Balance, analytical (0.001g precision) 5 Balance, electronic or manual (0.01g precision) 1 pkg of 50 Balloons, latex 4 Beakers, 50 mL 4 Beakers, 100 mL 2 Beakers, 250 mL Developed by California Science Teachers Association to support the implementation of the California Next Generation Science Standards. Approved by the CSTA Board of Directors November 17, 2015. Quantity per Quantity per lab classroom/ Description group adjacent work area 2 Beakers, 400 or 600 mL 1 Beakers, 1000 mL 1 Beaker tongs 1 Bell jar 4 Bottle, carboy round, LDPE 10 L 4 Bottle, carboy round, LDPE 4 L 10 Bottle, narrow mouth, 1000 mL 20 Bottle, narrow mouth, 125 mL 20 Bottle, narrow mouth, 250 mL 20 Bottle, narrow mouth, 500 mL 10 Bottle, wide mouth, 125
    [Show full text]
  • Putting Chemicals Into Groups – Practical Guidance
    Putting chemicals into groups – Practical guidance There are three practical activities in this piece of work, an introductory demonstration, a class practical, and finally a second demonstration to show students the techniques that they will not be using for themselves Equipment and materials For introduction: heating salt and sugar Eye protection Bunsen burner Tripod, gauze, heat resistant mat Bottle tops or other small container for heating small amount of substance Table salt (NaCl) Sugar For class practical: per group of students Eye protection Bunsen burner Tripod, gauze, heat resistant mat Bottle tops or other small container for heating small amount of substance 100 cm3 (or smaller) beakers Small spatulas Stirring rod Test tubes Mineral wool Access to a fume cupboard (optional) The chemicals: These should be in small bottles, labelled with the letter given only. Students must be told not to heat H or J except in very small quantities in the fume cupboard. A salt – sodium chloride G wax B silicon H iodine C copper I sand (silicon dioxide) D washing soda/sodium carbonate J sulfur E sugar K carbon F aluminium For demonstration: Filter papers Circuit tester – or power pack, leads, crocodile clips, graphite electrodes and light bulb in holder Iron nail Cyclohexane (Highly flammable, harmful, dangerous for the environment) Test tubes and bungs Small spatulas Nuffield Practical Work for Learning: Argumentation • Putting chemicals into groups • Practical guidance page 1 of 4 DRAFT pre‐publication pilot material NOT FOR DISTRIBUTION © Nuffield Foundation 2012 • downloaded from www.nuffieldfoundation.org Putting chemicals into groups – Practical guidance Health & Safety and Technical notes Before carrying out this practical, users are reminded that it is their responsibility to carry out a risk assessment in accordance with their employer’s requirements, making use of up‐to‐date information.
    [Show full text]
  • Laboratory Equipment Used in Filtration
    KNOW YOUR LAB EQUIPMENTS Test tube A test tube, also known as a sample tube, is a common piece of laboratory glassware consisting of a finger-like length of glass or clear plastic tubing, open at the top and closed at the bottom. Beakers Beakers are used as containers. They are available in a variety of sizes. Although they often possess volume markings, these are only rough estimates of the liquid volume. The markings are not necessarily accurate. Erlenmeyer flask Erlenmeyer flasks are often used as reaction vessels, particularly in titrations. As with beakers, the volume markings should not be considered accurate. Volumetric flask Volumetric flasks are used to measure and store solutions with a high degree of accuracy. These flasks generally possess a marking near the top that indicates the level at which the volume of the liquid is equal to the volume written on the outside of the flask. These devices are often used when solutions containing dissolved solids of known concentration are needed. Graduated cylinder Graduated cylinders are used to transfer liquids with a moderate degree of accuracy. Pipette Pipettes are used for transferring liquids with a fixed volume and quantity of liquid must be known to a high degree of accuracy. Graduated pipette These Pipettes are calibrated in the factory to release the desired quantity of liquid. Disposable pipette Disposable transfer. These Pipettes are made of plastic and are useful for transferring liquids dropwise. Burette Burettes are devices used typically in analytical, quantitative chemistry applications for measuring liquid solution. Differing from a pipette since the sample quantity delivered is changeable, graduated Burettes are used heavily in titration experiments.
    [Show full text]
  • Bunsen Burner Lab Bunsen Burner
    Bunsen Burner Lab Gas regulator knob Name: _____________________________________________ Period: ________ Date: __________ Score:_________ I. Background—Parts of the Bunsen burner Name of Part Function Barrel Air intake openings (holes) Needle valve Gas regulator knob Base Gas intake tubing Gas valve II. Burner flame characteristics A) Close the air holes at the base of the burner. The flame now has a(n) _________________________________ color. This is called a luminous flame. With the crucible tongs, hold a dry porcelain evaporating dish in the tip of the flame for about a minute. A(n) __________________________________________ color deposit of what appears to be ____________________________________ forms on the dish. This deposit comes from the incompletely burned gas. B) Now open the air holes and note the change in the appearance of the flame. The flame now becomes a(n) ____________________________________ color. This is called a nonluminous flame. (NOTE: If too much air is admitted, the flame may “strike back” and burn at the base. If a burner strikes back, the gas must be turned off, the air supply decreased, and the burner relighted.) Regulate the air and gas supply so that the flame is as colorless and quiet as possible. Clean the evaporating dish by means of water and a paper towel and hold the DRY dish in this nonluminous flame. Does the bottom of the dish now become coated as before with the luminous flame?________________________________________________ Bunsen Burner Lab Gas regulator knob Name: _____________________________________________ Period: ________ Date: __________ Score:_________ I. Background—Parts of the Bunsen burner Name of Part Function Barrel Air intake openings (holes) Needle valve Gas regulator knob Base Gas intake tubing Gas valve II.
    [Show full text]
  • Science Notes Higher Level Mandatory Experiments
    Mandatory Experiments Science Notes JC-Learn JC-Learn Science Notes Higher Level Mandatory Experiments 1 | P a g e Mandatory Experiments Science Notes JC-Learn Mandatory Experiments This folder includes every single experiment, which you must complete throughout the course. You must then write up these experiments in your experiments book and this is worth 10% of the exam. Biology Mandatory Experiment *To investigate the variety of living things by direct observation of plants and animals in their environment. To classify living things as plants or animals, and animals as vertebrates or invertebrates. Materials needed: Plant and animal identification books, plant and animal keys, notebook and pencil Method 1. Select area (school grounds) 2. Look for as many examples of plants and animals as you can find 3. Using identification books and keys, identify and name three plants and three animals within the area 4. Note which animals are vertebrates and which are invertebrates 5. Record the information Method 1. Use forceps to take small piece of inner skin of onion 2. Put drop of water onto glass slide, put piece of onion skin onto drop of water on slide 3. Lower cover slip over the onion skin (protects microscope lens) 4. Put slide onto microscope stage, under the clips 5. View the slide through the lens 2 | P a g e Mandatory Experiments Science Notes JC-Learn 6. Draw and label diagram of few cells under low power, then under high power 7. Remove slide from stage 8. Put drop of iodine stain under cover slip (stains the cytoplasm into yellow/brown colour) 9.
    [Show full text]
  • Modern Bunsen Burners Distribution System Should Not Be Underesti- Mated
    Modern Bunsen burners distribution system should not be underesti- mated. A major source of danger is posed by Introduction leaking systems, causing highly flammable gas to escape. Furthermore, accidents are caused Flame sterilization is a routine task carried out in by unattended burners and the fact that the hot many microbiological, clinical and life science blue flame is often barely visible. laboratories. Bunsen burners provide a flame with temperatures up to 1’200°C. Natural gas Accidents caused by burners are relatively rare, (primarily methane), liquefied petroleum gas but when they do occur they are often devastat- such as propane, butane or a mixture of both ing, resulting in severe injuries or fires. No won- are used as fuels. The gas flows through a small der, safety officers are keen to encourage labo- opening at the base of the barrel and is directed ratory staff to avoid open flames whenever pos- upwards. Air vents at the tube bottom permit air sible. to enter the gas stream by the Venturi effect. The amount of oxygen (air) mixed with the gas stream defines the completeness of the combus- There is a safe alternative! tion reaction. Thus, a gas stream well mixed with Safety Bunsen burners were developed to oxygen results in a complete and hotter reaction reduce dangers as described above. The than with less oxygen. The air rich flame ap- following features make them safe burners: pears blue and creates a roaring noise whereas an incomplete combustion results in a noiseless Flame monitor and yellow flame (see figure below). The highest temperature within the blue flame is obtained at To prevent dangerous gas leakage, safety the tip of the inner cone.
    [Show full text]
  • General and Inorganic Chemistry
    GeneralEquipment. and inorganic LD chemistry Chemistry Air and other gases Leaflets C1.4.2.1 Production of gases Production of gases with a Kipp’s apparatus Aims of the experiment To learn a method for producing gases. To work with the Kipp's apparatus. To follow a reaction. To observe the various aggregate states of substances. passes through to the zinc, both substances can react with one Principles another and hydrogen is generated. The gaseous state is one of the three states of aggregation in The following reaction occurs: addition to the solid and liquid state. The particles contained in + 2+ a gas move freely at a large distance from one another. Thus, Zn+ H → Zn + H2 ↑ there is no solid structure in gases. They use the entire space The special feature of the Kipp's apparatus is that the reaction made available to them and are limited only by the walls of a can be stopped by closing the stopcock, and it can be restarted storage container, for example. by reopening it. The reason for this is that when the stopcock Many gases are generated through the reaction of various sub- is closed, gas being generated can no longer escape. This stances, such as a liquid and a solid substance. This includes causes the pressure to increase inside the apparatus and the hydrogen, oxygen, chlorine gas, nitrogen dioxide or carbon liquid is pushed back through the insert tube with the frit into monoxide, for example. the flask. The reaction stops as soon as the liquid, in this case hydrochloric acid, can no longer reach the zinc granules.
    [Show full text]
  • Phytoplankton Culture for Aquaculture Feed
    Southern regional SRAC Publication No. 5004 aquaculture center September 2010 VI PR Phytoplankton Culture for Aquaculture Feed LeRoy Creswell1 Phytoplankton consists of one-celled marine and digestibility, culture characteristics, and nutritional value freshwater microalgae and other plant-like organisms. (Muller-Feuga et al., 2003). They are used in the production of pharmaceuticals, diet supplements, pigments, and biofuels, and also used as Table 1: Cell volume, organic weight, and gross lipid content of feeds in aquaculture. Phytoplankton are cultured to feed some commonly cultured phytoplankton species used in bivalve mollusc and fish hatcheries (Helm et al., 2004). bivalve molluscs (all life stages), the early larval stages of Species Median cell Organic Lipid crustaceans, and the zooplankton (e.g., rotifers, cope- volume weight content (%) pods) that are used as live food in fish hatcheries. (μm3) (pg) Flagellates and diatoms are two important types of FLAGELLATES phytoplankton at the base of the food chain. They manu- Tetraselmis suecica 300 200 6 facture cellular components through the process of pho- Dunaliella tertiolecta* 170 85 21 tosynthesis, taking up carbon dioxide and nutrients from Isochrysis galbana (T-ISO) 40 – 50 19 – 24 20 - 24 the water and using light as an energy source. DIATOMS The microalgae used as feed in hatcheries vary in size, environmental requirements, growth rate, and nutrition- Chaetoceros calcitrans 35 7 17 al value (Fig. 1, Tables 1 and 2) (Helm et al., 2004). When Chaetoceros gracilis 80 30 19 selecting a species for culture, it is important to take all Thalassiosira pseudonana 45 22 24 of these parameters into consideration. Most hatcher- Skeletonema costatum 85 29 12 ies grow a variety of species that serve different needs Phaeodactylum tricornutum* 40 23 12 throughout the production cycle with respect to size, * Species considered to be of poor nutritional value.
    [Show full text]