Bunsen burner and attached tubing, striker, evaporating dish, wire gauze pad, tongs.

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1 LABORATORY PROCEDURES OBJECTIVES: To observe proper safety techniques with all laboratory equipment. To use laboratory apparatus skillfully and efficiently. Before you actually complete an experiment, you must know how to properly use the laboratory equipment. The majority of the lab experiments, use a bunsen burner, measure volumes of liquids, mass out solids on a balance and filter materials correctly. Please read every procedure carefully!! Use all safety precautions and listen to your teacher's instructions carefully. Your performance in this lab, usually tells your instructor what kind of year you will have in the laboratory. LETS MAKE THIS A GOOD YEAR FOR ALL OF US!!!! SAFETY: Goggles and aprons are to be worn at all times.. PARTl Materials: THE BURNER Bunsen burner and attached tubing, striker, evaporating dish, wire gauze pad, tongs. copper wire Make sure you record all observations. PROCEDURES: 1. A bunsen burner is made up of a base and a barrel. The barrel can be turned to add or remove oxygen. To add oxygen, turn the barrel counter clockwise. To remove oxygen, turn the barrel clockwise until it won't turn any more. Practice both ways, then turn the barrel so oxygen is not added. 2. Connect the burner with the tubing to the gas spout on the lab table. Practice using the striker so you develop a good spark. Make sure you push and slide the striker over to form a spark. Practice this now. 3. Turn the gas valve knob so its lined up with the gas spout. You should hear a hissing sound. Place your striker close to the top of the barrel and produce a spark. A yellow flame should appear in the burner. To lower the flame height, slowly turn the gas valve knob. To change the yellow flame to blue, you must add oxygen. Slowly turn the barrel counter clockwise, notice the flame turns blue. Stop turning the barrel when you have a blue flame. If the flame goes out, you turned the barrel too far. You will have to start all over. If your flame goes out, make sure youturn off the gas from the valve!! 4. Using the inner part ofthe blue flame which is also called the "nonluminous flame" It is the hottest part of the flame. Using your tongs, take a piece of copper wire and hold it in the inner blue flame. Write down what you observe. Remove your copper wire which is very hot and run it under water, then you may throw it away in the garbage. t

2 5. Turn the barrel clockwise to change the flame from blue to yellow. Using your tongs, place the bottom of the evaporating dish under the yellow flame for 2 minutes. Write down what you observe. Put the evaporating dish on your gauze pad which should be on the lab table to cool. 6. Turn off the gas from the valve, remove the tubing from the valve, and let the burner cool. Clean the evaporating dish with soap and water. PART 2 THE BALANCE Balance Material: Sodium chloride 1. Never place chemicals on the balance pan. Use weighing paper or a weighing cup or pan to place the chemicals in. 2. Measure an empty plastic cup on the balance. Record your value, make sure you end the number with the unit grams. 3. Get a sample of salt from your teacher. Write down the sample number down on your paper. Measure the cup with the salt on the balance, record your value. 4. Determine the mass of the salt. 5. Return the cup with the salt to your teacher. PART 3 MEASURING LIQUIDS 1. When measuring volumes of liquids, you will always use a graduated cylinder. Never a beaker or flask. Cylinders come in different 'sizes, 10mI and 100ml graduated cylinders is what you will be using in this class. 2. To properly read an amount ofliquid, you must get eye level with the level ofliquid in the cylinder. You locate the "dip" in the liquid and read the line that the dip is on. The dip is called the meniscus. If the meniscus is between lines, you approximate 0.5 ml. Each line on the cylinder represents a milliliter. 3. Your teacher has two graduated cylinders on the lab table in the front of the room. Read the volumes of both liquids and record your results. 4. Use the thermometer on the teachers desk, take the temperature of the liquid that is in the large graduated cylinder. t

3 PART 4 FILTRATION Ring stand, Ring clamp, clay triangle, funnel, piece of filter paper, 250ml beaker, 400mlbeaker Material: Mixture from teacher. 1. Set up the filtration system see example: - _. eja..rn? 2. Fold the filter paper in half, then in half again. Now you have a cone, open the cone by 3 parts of the paper on 1 side and 1 part on the other side. Place the filter paper in the funnel Sprinkle a few drops of water on the paper so it will stick to the funnel. 3. Bring your 250ml beaker up to the hood. Get a sample of the mixture from your teacher. 4. You will filter out the solid from the liquid by pouring the mixture into the funnel. Do not pour too much mixture so that it over flows!'. Make sure you stir your mixture before you pour it into the funnel. 5. When you are done, your liquid in the collection beaker should be clear. This is called the filtrate. Using your graduated cylinder, measure the volume of filtrate you have collected. Record your volume. 6. Throw out the filter paper in the garbage, put the liquid in the sink. Clean and put all equipment away. Clean your lab table and wash your hands.,.

4 ~r Observation and Data Sheet Observations of the copper wire: Observations of the evaporating dish: Data: 1. Mass of empty plastic cup g. 2. Sample # Mass of cup + salt g. 3. Mass of salt g, 4. Volume of liquid in large cylinder.ml. 5. Volume of liquid in small cylinder ml. 6. Temperature of water in large cylinder e Volume of filtrate ml -----',.

5 QUESTIONS: Answer all questions in complete sentences. 1. As soon as you enter the lab, what safety equipment should you put on immediately? 2. Before doing an experiment, what should you read and discuss with your teacher? 3. What immediate action should you make when the flame of your burner has been extinguished? 4. What type of flame is preferred for laboratory work and why? 5. Why are chemicals and hot objects never placed directly on a balance pan? 6. What is the proper way to read the volume of any liquid? 7. What is the collection liquid called after you complete a filtration? 8. How should you dispose any solids or liquids used in a lab experiment? 9. Why are broken glassware, chemicals and matches never thrown away in a wastepaper basket? 10. In what condition should all lab equipment be stored at the end of the experiment? "