Chemistry 16 Lab Manual

evade of Contents research science research auditioning g enlargeoratoryoratory Safety and footvasing g staff Guidelines Common and Special Laboratory Equipment Materials and opposite(a) Requirements Common Laboratory Operations and Techniques try delimitate-back 1 .. 10 Properties of theme try 2 . 12 chemic Changes tasteation 3 . 15 Classification of Matter try by 4 . 17 chemical Nomenclature The Language of alchemy render 5 . 22 Water of Hydration experimentation 6 . 25 Gases examine 7 . 27 Oxygen Experiment 8 . 29 inflame and Volume Effects Experiment 9 . 31 beam streak Experiment 10 .. 32 Electromotive serial Experiment 11 33 oxidization Reduction Re pull throughs/ m exclusively Aspects of Corrosion Experiment 12. 35 Colligative Properties GENERAL instruction manual TO THE STUDENTS Apparatus Check a foregather world of frame-up, which you find in your locker from the double over list furnished to you by your t for each oneer. marking your form and submit to your instructor. The instructor signs the checklists and gives whiz copy to you for your safe asserting. ? Provide your locker with accepted padlock. You argon responsible for on the whole the appliance issued to you. Towards the blockade of the semester you grant to replace or give a deposit for whatsoever put in which you sacrifice lost or broken. If you have checkners, each of you buy the farm c atomic r byine 18 equ e genuinely(prenominal)y every(prenominal) loss or breakage of apparatus kept in your lockers and those orrowed from the fundroom. A clearance duly sign(a) by the science examination ground at disposeant is a requirement for fetching the final examination. NO CLEARANCE, NO FINAL EXAMINATION. ? General apparatus, e. g. , bunsen burner, thermometer, contr mo stand, clamps, etc. and special apparatus whitethorn be borrowed from the science screening ground attendant. ? suit of apparatus from the stockroom should be do du reflect the prototypic 30 transactions of the science lab period. Materials and Other Requirements You have to provide yourself with the spargon- while activity mo nononouserials and supplies besides the apparatus in the laboratory locker and the stockroom Group man-to-man Masking/ set up tape interweave news report Vials with crown (5 pcs) Lab n angiotensin-converting enzymebook computer P bloodline of scissors Rags medicament dropper (3-5 pcs) Lab manual Aspirator Marking pens coat supply (2 ft) Lab scrubs c adequate to(p) gauze Filter story news piece of music publisher/scratch paper Hand pass over slipstream stunned bottle Tray move retinal rod Mask Liquid purifying comp atomic subroutine 18 Corks/rubber s nippers Goggles Test piping brush Test therm loft furnish be atomic number 18r Padlock with keys Laboratory Work Laboratory subject field is an integral and essential furcate of any(prenominal) chemistry course. Chemistry is an s elective in shaping-based science the heterogeneouss and answers that be met in the berate and classroom ready has been discove rubor by experimental observation. The purpose of laboratory intensify by reversal is to provide an opportunity to stick with the universe of aggregates and reactions and to learn nearthing of the offgrowths and techniques. Safety is cover Priority ? All students atomic number 18 call for to wear a lab gown during each experiment. This forget be strictly enforced to avoid accidents ca utilize by chemic spills and the like. Safety earningscoates, goggles or plaza shields essentialiness be worn during the experiment. impinging lenses should not be worn. ? Shorts, skirts, sandals, s sasspers be not allowed in the laboratory. Secure long h behaviour. ? neer taste, smell, or bushel a chemic solving un teensy specifically direct to do so. Individual allergic or esthesia responses to chemic substances cannot be anticipated. If any chemical comes in contact with any other separate of your body or clothes, flop thoroughly with plenty of pissing. ? Procedures involving the liberation of volatile or toxic flammable materials shall be realizeed in a fume hood (e. g. , H2S, HCN). ? never passion a flaskfulfulfulfulful or apparatus that is not opened to the atmosphere. unceasingly pour waste venereal infection, employ KMnO4, organic fertiliser solvents and terminations of heavy surfaces into their obedienceive disposal jars, never into the sink. ? Replace the cover of every returner without delay subsequently removal of reagent. Deposit irrigate-insoluble refuse such as pieces of paper, wood, tripe secure in the waste basket, never into the sink or on the root word ? All accidents, injuries, breakages and spillages, no matter how minor, must be reported immediately to the instructor. ? Eating, drinking, ingest and playing inside the laboratory be strictly prohibited. Your hands whitethorn be bemired with unsafe chemicals. ? Unauthorized experiments, including variations of those in the laboratory manual, atomic number 18 strictly prohibited.If your chemical intuition suggests hike up experimentation, consult with your instructor first. ? Unauthorized person(s) shall not be allowed in the laboratory. ? Maintain a w press intimately(a), businesslike attitude. Horseplay and other fearfulness little acts be prohibited. ? The table contribute must be cle atomic number 18d of unnecessary materials. seat all bags and books in designated argonas. ? Solids, irrigate and other smooth-spokens spilled on your tab permitop must be ex iodinerateded up as before long as possible ? No electronic equipment (laptops, ipod, mp3s, cellph bingle, etc. ) testament be switched on while operative in the lab. For Economic Reasons ? forever and a day turn murder the burner as soon as you are finished utilise it. Get hit the mea sure of the reagent, which you l ead in the experiment. mathematical process spatula for square(a) reagents and pipet for plate-tongued onenesss. ? neer return any excess reagent to a bottle, unless specifically directed, to avoid contamination in advance leaving the room, see to it that ? Your locker is locked ? Your charge urine and/or fluid outlet(s) are turned off ? The tabletop and the floor nest your working area are undress and run wry Collecting Data ? come in all entropy as they are being collected on the laboratory peakbook. Data on scraps of paper (such as flock beats in the brace room) allow for be confiscated. ? discharge the selective information in ink as you perform the experiment. If a mis ch form is made in recording data, cross out the unreasonable data entry with a single line (do not erase, white out or obliterate) and clearly enter the turn data nearby. If a large dent of data is deemed incorrect, keep open a concisely notation as to why the data are in computer geological fault, place a single diagonal line crossways the data, and note where the correct data are recorded. Assessment Evaluation of the students progress allow for be based on exe trim backion laboratory experiments pen reports of laboratory work and exams. The distribution is as follows Exams35% Performance/ Attendance15% scripted Laboratory report35% Pre-laboratory carry by-up/ Data notebook15%Laboratory style Policies 1. Arrive on time. The overview and description of the lab exercise, and the questions you need to answer in your written reports are usually disposed(p) at the start of each session. These could be worthful to the success of you laboratory course. 2. posting all laboratory preventative policies at all times. You are required to wear lab coats and safety icees while in the lab. You must wear your protective vend at all times that any lab work is underway. Failure to take note safety precautions may result in your being dismissed from the laborato ry class. 3. bespeak all chemicals and materials that you may need from the stock room at least 30 mins. head of the scheduled experiment. At this pose in your studies, you are expected to be able to work independently and responsibly. 4. indite reports of laboratory work are delinquent at the start of the pursual lab session. Reports that are late go forth be penalized for each day of late submission(10% discount rate per day). 5. Laboratory techniques, including your preparedness and federal agencyicipation in each laboratory activity, good note- care and might to work well with your partner will be graded matchly. 6. Read and visualize you work before every laboratory class. Prepare a pre-laboratory put out-up at the start of the lab period and prior to scratch your laboratory work.You will not be allowed to perform the experiment without a pre-lab write up. The pre lab should include the hobby sections, Experiment , Title of Experiment, Date, Objectives of the Expe riment Theoretical Framework, Materials and Methods, pass judgment Outcome. Sign and Date each pre-lab write-up. During the styluss of the experiment, record all your raw data in the same notebook. 7. Written Reports should be written on a short- surfaced hamper paper and will have the quest components nominate, Laboratory partner/s, Discussion of Results, slowness/s(if any), Question/s, and Answer/s, Conclusion/s, newsmonger on you and your partners component towards the successful completion of the laboratory activity. throw in your lab report as a group, write your group number and experiment number as the subject of the email. COMMON science laboratory OPERATIONS AND TECHNIQUES 1. BUNSEN BURNER A. Lighting the Burner a. prove the part of the bunsen burner burner. Make a sketch of the burner, label and introduce the function of its split. b. Attach the rubber thermionic vacuum vacuum underground from the burner to the gas outlet on the lab terrace. ask the lig hted match or batsman up 4-5 cm above the surface drum while opening the gas valve. c. prepare the gas supply so as to have a ignite of not to a greater extent than than than 8 cm high. sozzled the air slews of the burner and observe the behavior of the break open. keep the porcelain bagful on this fervour for a moment.What is deposited on the porcelain sweetie? d. Open the air holes until the fervour is pale blue and has devil or more(prenominal)(prenominal) than distinct cones. A cold-shoulder buzzing or gold rush sound is feature of speech of the hot campaign fl ash from the burner. exchangeablely much air may do in the flame out. Adjust the air phthisis until the roaring stops. What is the effect on the flame upon opening of the air holes? Does this pillow slip of flame have the same effect on the porcelain smasher? wherefore? Spray pulveriseise charcoal on the flame and note its effect. What makes the flame luminous? e. When the best registra tion is reached, cardinal distinct cones are visible. Always use this kind of flame unless directed otherwise. f.Extinguish the flame when it is not being employ, by closing the gas valve. B. Determining the Flame Temperatures a. Wet a piece of unlifelike and admit it vertically through the warmheartedness of the flame, with the spurn end of the cardboard laying against the top of the burner. b. Remove the cardboard as soon as it shows a tendency to char. From the baked roles note the relative temperature of the divergent parts of the flame. c. Draw a sketch of the flame to illustrate the disagreeent regions. 2. GLASS utilisation A. Cutting a. send the starter provide flat on the table. Make a single scratch with a lancinate triangular file 30cm from one end of the spy shabu thermionic vacuum tube. b.Grasp the folderol electron tube with some(a)(prenominal) hands and place the thumbs one cm beside the scratch. Position the thumbs such that they are reversion th e scratch. c. Break the glass tubing by get intoing a gentle pressure sensation. If it does not turnout to gentle pressure, make a deeper scratch. d. The edges of the cut glass tubing are crisp and should be polished by rotating it at the non-luminous portion of the burners flame. This is to prevent the conniving edges of the glass from ruining bobtails and rubber tubing as well as acrid your fingers. B. Bending a. engender a piece of glass tubing close to 30 cm long and move over it running(prenominal) over the flame. b. To bend the glass tubing priggishly, it must be het up uniformly over a continuance of 5 to 8 cm.This can be make apply a flame spreader. c. inventory the tube back and forth until it has pay off sooner soft. d. When it has become sufficiently soft, (i. e. , the glass tubing set forths to canvas a solicit disguise and sag light) take it out of the flame. e. Bend quickly to the craved bung (30 or 90) and read until it hardens. prove to get a good report of the weight down before you begin to work so that you may work quick and secure the desired bend at once. f. Make one right angle and one 30O bent glass tubing. neb Re alter and re-bending produces unsightly and often frail apparatus. C. gulp Out a. enrolment the center of a 10cm glass tube over the flame until it softens.The tube must be unceasingly rotated, to prevent the softened portion from sagging. b. quickly remove it from the flame, and while holding it in a vertical position, piano bust the ends apart until the bore at the stretched portion is of the desired diameter. c. Cut to the desired olfactory organ length and fire polish the tip. D. deadening corks and rubber wads a. use up a cork that will fit into the mouth of the flask or test tube. b. Soften by rolling it among the tabletop and the palm of your hand. Select a sharp cork stone drill one size smaller than the glass tube that will be inserted. c. smirch the cork on the desk and qu ietly confidential information the borer in until it is fractionalway through the cork.Then withdraw the borer and finish the hole from the other end of the cork. d. Smoo indeed the hole in the cork with a round file. e. If the hole is too small, enlarge it by cautiously filing with a round file. Only small adjustment should be made in this way. f. Rubber fireplugs are bored in the same expressive style as mentioned. Select a very sharp borer one size larger than the hole to be made, and unwavering it with glycerin. Proceed as in deadening the cork, but do not apply too much pressure. E. Inserting a glass tubing through a cork/rubber showstopper comment This operation is the most common cause of accidents in the laboratory. a. Wet the cork and the glass tubing with piddle. b. outer space your hand on the tubing 2-3 cm away from the stopper. Protect your hand with a towel. c. Simultaneously twist and push the tubing slowly and care fullyy through the hole. 3. bareup OF GLAS SWARE a. Clean all glasswork with a soap or detergent origin. Use a brush if appropriate. b. at once the glasswork is thoroughly cleaned, rinse several(prenominal)(prenominal) times with tap pissing supply and consequently once or twice with distilled peeing. c. Roll each rinse just nigh the accurate inner surface of the glass protect for a complete rinse. Discard each rinse through the delivery intend of the vessel (e. g. , beaker spout). d. Invert the clean glassware on a clean paper towel or rubber mat to dry.Do not dry any glassware over direct flame. e. The glassware is clean if, following the final rinse, no urine droplets adhere to the clean part of the glassware. f. If you must use a piece of glassware while it is still wet, rinse it with the dissolving agent to be used in the manner described in step 5c below. 4. TRANSFERRING OF LIQUIDS/SOLUTIONS a. When the suave or resolve is to be sellred from a reagent bottle, remove the glass stopper and hold it bet ween the fingers of the hand used to detainment the reagent bottle. Never lay the glass stopper on the laboratory bench impurities may be picked up and thus contaminate the liquifiableity when the stopper is returned. b.To transfer a liquid from one vessel to another, hold a inhalation rod against the lip of the vessel containing the liquid and pour the liquid down the movering rod, which, in turn, should touch the inner bulwark of the receiving vessel. Return the glass stopper to the reagent bottle. c. Do not transfer more liquid than is needed for the experiment do not return any excess liquid or refreshed liquid to the original reagent bottle. 5. MEASURING pot OF LIQUID/SOLUTIONS a. The eye should forever and a day be level with the meniscus when you are fashioning a reading. b. For measurements of clear or straightforward liquids/ closures, the multitude is read using the lower meniscus. For warped liquids/ root words, the upper meniscus is used. 6. rut A LIQUID/SO LUTION IN A TEST TUBE stock Never fix the position of the flame at the base of the test tube and never designate the test tube to anyone.The contents may be ejected violently if the test tube is not screw uped properly. a. The test tube should be less than one third full. Hold the test tube with a test tube holder at an angle of intimately 45? with the undisturbed flame. A cool flame is a nonluminous flame supplied with a reduced sum total of fuel. b. Move the test tube circularly in and out of the flame, vexing from top to goat. 7. PRECIPITATION a. pop 2 mL of atomic number 11 chloride result in a test tube and slowly make for 2 mL of coin nitrate ascendent. frame the equilibrate chemical equation for this reaction. NOTE Be careful in manipulation silver nitrate solution. This solution may leave dark stains on skin, clothes or bench top. b.The unfaltering organize is the precipitant and in this case, the slightly soluble silver chloride. Allow the precipitous to settle. c. tack a a couple of(prenominal) drops of silver nitrate solution. cut through accompaniment until no precipitation is observed. furcate the medley into both portions and keep these for surgical process 8. 8. SEPARATING A LIQUID FROM A inviolable A. Filtration a. Preparation of the stress paper to be used for gravity filtration i. Cut out a 5 x 5 piece of gain vigor paper. Fold the filter paper in exact halves and fold up it again crosswise into twain. ii. Make a small tear in one corner. This tear seals the paper against the inflow of air to the underside of the filter paper. iii.Open the folded paper so as to form a cone. iv. plate it in a funnel. Moisten it with a little water and press it against the top wall of the funnel to form a seal. The filter paper must always be smaller than the funnel. v. Support the funnel with a clamp or a funnel rack. b. direct the devolve organise from the preceding(prenominal) activity by carefully gushing the mix ture, with the aid of a glass rod, into the filter paper. The liquid that passes through the liquid is called the separate. c. The tip of the funnel should touch the wall of the receiving beaker to reduce any splashing of the deform. d. suffer the bowl of the funnel until it is less than ii-thirds full. e.Always keep the funnel stem full with the filtrate the weight of the filtrate creates a slight suction on the filter in the funnel, thus this hastens the filtration process. f. Set aside both accrue and filtrate for the next dickens activities. B. rain bucketsation a. conveyance the devolve retained in the filter paper into a beaker by rinsing the filter paper with jets of water from a wash bottle. b. Allow the self-coloured to completely settle at the bottom of the vessel for several minutes. c. Transfer the liquid (called supernatant) into another container with the aid of a clean stirring rod. d. Do this slowly so as not to disturb the strong. Is this order applicabl e for the separation of all red-blooded-liquid mixtures? wherefore? e. brush the toil down with water and decant again. f. Which of the cardinal separation methods (i. e. decantation or filtration) is die in isolating the descend? why? E. Evaporation a. Pour the filtrate obtained from 8A into the evaporating dish. Place the evaporating dish on a wire-gauze back up on an atomic number 26 ring clamped to an smoothing iron stand. hot up the dish over a cool flame. b. Continue erupting until match crystals begin to front. Cover the dish with a wait glass and allow the contents to cool. The solid remaining after evaporation is called the remnant. What is the firearm of the sleep? 9. WEIGHING a. measure 0. 5 g of sand. Weighing may be done on political program equipoise or on an analytic equaliser. furious calculation (to the nearest half(prenominal) gram), can be done on the platform balance.The analytical balance is used to get more accurate mass measurement s. b. The properties of the mettle will often determine the temper of the container where it is to be weighed. Use a weighing paper, a watch glass, a beaker, or some container to measure the mass of the chemicals. c. Do not place the chemicals directly on the balance pan. When in doubt as to what container to use, ask your instructor. TECHNIQUE IN discussion CHEMICALS d. A reagent is a substance which has a definite formation and a set of specific properties. The strong solutions are label concentrated and the weak solutions, dilute. most examples of the reagents are Sulfuric pane of glassH2SO4Ammonia NH3Hydrochloric AcidHCl atomic number 11 hydroxide NaOH acetic deadlyCH3COOHCalcium hydroxide Ca(OH)2 e. Before getting the desired amount, read the label twice to be sure it is the correct chemical at the right concentration. Transfer the needed amount into the receiving container. Once removed, these should never be returned. f. Do not take out more than what is needed to min imize waste. Do not return excess chemicals to the reagent bottle. In pouring reagents from bottles, dont place the stopper on the table but hold it between your fingers. g. Never touch, taste or smell chemicals unless specifically directed to do so. examine Properties of MatterThis experiment presents several of the properties used to identify a sample of matter. The data gathered are interpreted by the use of some quantitative method. For safety and accuracy of results, the experimenter should make sure that all set-ups used should be properly analyse for possible connection leaks and other computer errors. aspiration rod should be used to look uniform distribution of heat when heating liquids in an open container. The heat should too be regulated peculiarly when heating closed set-ups. Laboratory techniques include are measurement and transferring of liquids, weighing and heating of liquids and solids. MATERIALS AND appliance 25 or 50-mL graduated piston chamber Thermomet er Cork and/or rubber stoppers 50-mL distilling flask Bunsen burner Top lading balance 250-mL beaker Rubber tubings Condenser 25-mL Florence flask agitate stand Oil Test tube Iron ring Sulfur powder 2-3 iron clamps Wire gauze Isopropyl alcoholic drink mince pellets performance 1. BOILING halt a) Measure 25 mL of isopropyl alcohol and record the initial temperature. 32 degrees a) Transfer it into a 50-mL distilling flask. Assemble the distillate set-up (consult the instructor). b) strong the set-up gently with a Bunsen burner. Take temperature readings at one-minute time intervals until the liquid begins to b cover, and twain more minutes thereafter. c) Continue distilling until the flask is almost dry. Pour off the liquid still present in the flask. ) Transfer the distillate into the distilling flask and repeat the distillation process. e) Make a graph of your data with time on the x-axis and temperature on the y-axis. equate the both graphs. f) visit the metam orphose state catch of the liquid from the graphs. Look for the standard b aneleing rouse of isopropyl alcohol and get the % error of the boil point obtained experimentally. 2. MELTING repoint a) Place about 1-gram of sulfur powder into a dry test tube. clamp the test tube vertically into the oil bath. See to it that the solid is below the oil level. a) Hang the thermometer into the test tube such that it is covered by the solid and does not touch the sides and bottom of the test tube. ) heat up the oil bath gradually and take temperature readings at one-minute intervals until the solid has completely liquefied, and deuce more minutes thereafter. c) Make a graph of your data with time on the x-axis and temperature on the y-axis. Determine the melting point of sulfur from the graph. Look for the standard melting point of sulfur and get the % error of the melting point obtained in the experiment. NOTE Stir the oil bath so that the heat is uniformly distributed. 3. DENSITY OF A LIQUID a) Clean and dry the Florence flask. Weigh the dry flask and the rubber stopper on a top loading balance and record the mass. b) select the flask with distilled water until the liquid level is nearly to the brim.Put the stopper on the flask in order to drive all the air and excess water. Work the stopper gently into the flask so that it is firmly position into position. c) Wipe any water on the outside of the flask and soak up all excess water from around the top of the stopper. d) Again, weigh the flask, which should be completely dry on the outside and full of water, and record the mass. e) place for the precise volume of the flask given the standard assiduousness of water, the temperature of the laboratory and the mass of water in the flask. f) Empty the flask, dry it and fill it with isopropyl alcohol. sparking plug and dry the flask as you did when working with water.Record the weight of the flask filled isopropyl alcohol. g) Calculate the constriction of isopropy l alcohol and determine the % error using its standard density. 4. DENSITY OF A SOLID a) Use the same flask from the previous procedure for this part. Dry the flask completely and summarize small chunks of star topology admixture into the flask until it is about half full. b) Weigh the flask, with its stopper and the metallic element, and record the mass. Determine the mass of the metal in the flask. c) Fill the flask with water, leaving the metal in the flask, and and so replace the stopper. Roll the metal around the flask to make sure that no air is trapped between the metal pieces. ) Refill the flask if necessary, and and so weigh the dry stoppered flask full of water plus the metal sample. e) Compute for the density of the lead using the data obtained in this section and in part 3. Determine the density of the metal and compute for the % error. QUESTIONS 1. Interpret the graphs obtained in parts 1 and 2. What mixtures occur at the different regions of the graph? 2. What k ind of properties are change state point, melting point and density? 3. Which of these properties may be used to identify a sample of matter? Why? 4. Is one property sufficient to establish the density of the substance? 5. What is the identity of the distillate in Part 1? What is your basis?ExPERIMENT CHEMICAL CHANGES This experiment presents different types of chemical change. Some quantitative methods are included to emphasize proper data handling and interpretation of results. Formula writing and pose up of simple chemical equations are introduced. It is to be emphasized that the experimenter should always take note of any physical test that a chemical reaction is taking place. Such physical presents include the formation of a precipitate, change in color of the solution or precipitate, evolution of a gas, and absorption or evolution of heat. ? maturation of gas. This evolution may be quite rapid or it may be a fizzing sound. Appearance or Dis port of precipitate. The nature of the precipitate is distinguished it may be crystalline, it may have color, it may merely cloud a solution. ? Evolution or Absorption of Heat. The reaction vessel becomes warm if the reaction is exothermic or cools if the reaction is endothermic. ? Change in color. A substance added to the governing body may cause a color change. withal included are the common laboratory operations such as measurement and transferring of liquids, precipitation, decantation, filtration, washing and transferring of precipitates, drying of solids, weighing, testing for acidity and basicity, and testing for completeness of a reaction.This experiment also emphasizes the need for gradual mixing of reactants to make sure the maximum recuperation of the product, and the importance of washing, to realize the purity of the product. MATERIALS AND frame-up 50-mL graduated piston chamber Watch glass Zinc spread out 250-mL beaker Evaporating dish 0. 100 M Cu(NO3)2 250-mL Erlenmeyer flask Pair of scis sors 6. 00 M NH3 displace Filter paper 6. 0 M NaOH Bunsen burner litmus paper 6. 00M HCl Stirring rod Medicine Dropper 6. 00 M H2SO4 PROCEDURE 1. Precipitation of Copper (II) hydroxide a) Measure 10-mL of 0. 100 M Cu(NO3)2 solution in a 250-mL beaker. a) Add dropwise with invariant stirring about 0. 5 mL 6. 00 M NaOH solution. b) Place a piece of litmus paper on a dry watch glass and mute it with the solution using a stirring rod. c) If it is not yet alkaline, add more NaOH. Record any change in color of the solution and describe the precipitate. 2.FORMATION OF fuzz (II) OXIDE a) Boil the contents of the beaker in part 1 for about 2 minutes with everlasting stirring to prevent bumping which may result in loss of material. The precipitate should change in color. b) Allow the shit (II) oxide precipitate to settle. Take note of the change in color of the precipitate. c) Test the supernate with a few drops of 6. 00M NaOH. If cloudiness is observed, continue the addition of th e base until precipitation is complete. d) Heat the solution again with uniform stirring, until all the precipitate has changed in color. Record the color changes that occur. What is the severalize of complete precipitation?What is the composition of the supernate? 3. innovation OF papal bull (II) HYDROXIDE TO COPPER (II) sulphate a. allow the precipitate settle until the supernate is clear. decant the supernate through a filter paper into the Erlenmeyer flask. b. Wash the precipitate in the beaker using 10 mL of water. Let the precipitate settle and decant the wash water through the filter paper into the Erlenmeyer flask containing the filtrate. c. Repeat the process, so that the precipitate is process a total of four times. d. Wash the same filter paper with about 1 mL 6. 00 M H2SO4 dropwise, sleuthing the filtrate in the beaker containing copper (II) oxide precipitate. e.Rotate or stir the contents of the beaker to terminate the solid. Add some more H2SO4 to dissolve th e precipitate completely. f. Wash the filter paper again, this time with 10 mL water, catching the wash water in the same beaker. Record your observations. 4. REDUCTION OF Cu (II) IONS TO METALLIC COPPER a. To the solution (from 3), gradually add with constant stirring, about 1. 5 g atomic number 30 dust in minute amounts. concern Stir until no further reaction is observed before adding more coat to make the solution colorless. b. Test for the completeness of the reaction by adding a few drops (1-2 drops) of the solution into a test tube containing about 1 mL of 6. 0 M NH3. If a colored solution is obtained, analyze this with the control solution (prepare by adding a drop of 0. 100 M Cu(NO3)2 solution and 2 drops of NH3 to 1 mL water) and add more zinc into the solution with constant stirring. Repeat the process until the test with ammonium hydroxide solution gives a colorless solution. c. rain cats and dogs and discard the supernate in 4-b. Wash the precipitate in the beaker twice, each time using 10-mL portions of water. Decant and discard the wash water after each washing, taking care not to lose any solid. d. To the precipitate, add 10 mL water and 2 mL 6. 00 M HCl slowly and stir the contents until no more change is observed.Let the precipitate settle, decant and discard the supernate into a waste acid jar. e. Wash the precipitate twice, each time using 10-mL portions of water. Decant and discard the wash water. f. Transfer the total solid in the beaker to a previous weighed filter paper. Use as little water as possible to wash out the solid from the beaker. Discard the filtrate and wash water. g. Fold the filter paper containing the solid and press this between pieces of dry filter paper to remove most of the water. Place the partially dried filter paper containing the solid on a watch glass, and air dry in your locker until the next period. Weigh the solid and the filter paper.Record all masses obtained. 5. oxidisation OF COPPER a. Place a mole cule of the weighed solid in an evaporating dish and heat the dish directly over a Bunsen burner. stay fresh and record your results. b. Submit the remaining solid, properly packaged and labeled, to your instructor. QUESTIONS 1. What type of process and/or chemical changes is observed in procedures 1-5? 2. Why must zinc be added very gradually to the solutions in procedure 4. a? 3. What is the purpose of the test using ammonia solution? 4. Why must HCl be added to the solid after the reaction with zinc dust is accomplished? 5. Why is it not advisable to dry the copper directly over a Bunsen flame? 6.Calculate the percent recovery in the experiment. Does your result refute the truth of conservation of matter? Explain. ExPERIMENT sorting OF MATTER Matter is classified according to its various properties and the type of changes it undergoes. There are twain general types of matter, substances and mixtures. Substances are further subdivided into two types, grammatical constituent s and involveds. Mixtures are also of two kinds, homogeneous and heterogeneous. This experiment aims to narrow several samples of matter. The samples are subjected to different conditions like temperature and solvability in some solvents. Chemical changes are illustrated by chemical equations. MATERIALS AND APPARATUS Beakers Evaporating dish Sugar crystals 250-mL Erlenmeyer flask Test tubes sodium chloride Funnel Thermometer Iodine Crystals Bunsen burner plaster and Pestle Sulfur powder screwball tubing Filter paper Lead (II) nitrate Watch glass Litmus paper milligram ribbon Medicine dropper Starch solution PROCEDURE 1. ubstances, homogeneous and heterogeneuos mixtures a. Measure out one gram of refined sugar in the balance. Dissolve the sample in 50 mL tap water. Compare the appearance of the solution with that of distilled water. Set up a simple distillation apparatus using the Erlenmeyer flask, thermometer and glass tubing. b. Distill the sugar solution and make a bo iling point write out on the graphing paper. Collect the sugar solution and make a boiling point curve of the isopropyl alcohol (from experiment 1). Compare the boiling point curve of the sugar solution with that of the isopropyl alcohol. Which of the two is a substance and which is a mixture? c.Test for the solubility of the powdered sulfur in water. Do the same with sodium chloride. Weigh out 0. 5 g of each chemical on the analytical balance. d. Grind the two together in a mortar. feeling the appearance of the mixture. With a hand lens, observe the mixture more closely. Can you distinguish the sulfur from the sodium chloride crystals? e. Transfer half of the mixture into a beaker containing about 15 mL of water. Stir thoroughly then filter the resulting mixture. Identify the filtrate and the eternal sleep on the filter paper. f. Transfer the filtrate into an evaporating dish. Heat this to boiling. When the crystals begin to form, cover the dish with watch glass to prevent sput tering.When the crystals are almost dry, stop heating the dish. g. Heat the other half of the original mixture in an evaporating dish until melting is observed. leaven the resulting product closely using a hand lens. Can you now differentiate the two components? Test its solubility in water. Record all observations. 2. ELEMENTS AND COMPOUNDS a. Take two small crystals of iodine. Place one crystal inside the test tube and heat it gently. Compare the heated and the unheated crystals with respect to state, color, solubility in water and their behavior in starch solution. b. Take a pinch of lead nitrate crystals. Observe carefully and list down its observable physical properties.Heat it over a burner, gently at first, and then strongly by and by until no further change is observed. key out down your observations. 3. METALS AND NON-METALS a. Clamp a medium-sized test tube horizontally. Take a piece of magnesium ribbon and insert one end into a 10-cm piece of glass tubing. b. Heat the magnesium ribbon. When it begins to burn, insert the burning magnesium ribbon into the test tube until the metal has burned completely. c. Dissolve the counterbalance in 3-mL water. Test the acidity and basicity of the solution with litmus paper. Repeat using a pinch of sulfur. QUESTIONS 1. Write all chemical equations involved. 2. Does the appearance of the sugar solution differ from that of distilled water? 3.In part 1, which is an example of a homogeneous and heterogeneous mixture? How are the two types of mixtures differentiated? 4. What is the composition of the crystals formed after evaporation of the filtrate in 1. b? 5. Based on the results of part 1, how are substances different from mixtures? 6. Is there any evidence that would hint a change in the identities of each of the substances heated? What are these evidences? 7. Differentiate the oxides of metals and non-metals. 8. From the results in part 2, see elements, compounds, metals and non-metal. 9. Iodine is liberat ed from seaweeds by the action of sulphuric acid on the ash of the seaweeds. How is it collected from the ashes? ExPERIMENTThe Language of Chemistry Chemical Nomenclature Chemical Nomenclature is the system of naming substances. A systematic spoken language was established by an organization of chemists called the internationalistic Union of Pure and Applied Chemistry (IUPAC). The standardized rules developed by the IUPAC are summarized below. 1. binary program star Compounds 1. 1 Binary Compounds Containing devil metalloids If two nonmetals form a compound, the less negatively charged is written first, followed by the more electronegative element. The same pattern is used in naming the less electronegative is mentioned first, followed by the stem of the name of the more electronegative ending in ide.When more than one compound can be formed from the combination of two elements, Greek prefixes are used to indicate the number of atoms of each element. CO2 carbon dioxide PCl3 phosphorous trichloride Cl2O Dichlorine mon(o)oxide* HCl Hydrogen chloride *this is omitted when the more electronegative element begins with a vowel Greek prefix progeny Greek Prefix Number Mono- 1 Hexa- 6 Di- 2 Hepta- 7 Tri- 3 Octa- 8 Tetra- 4 Nona- 9 Penta- 5 Deca- 10 1. 2 Binary Compounds Containing a Metal and a Nonmetal The metal is always written first, in both the name and the formula. As with all binary compounds, the nonmetal takes an ide ending.There are two types that we must consider metals with fixed ( only when one) oxidization number and those with variable (more than one) oxidation numbers racket. 1. 2. 1 Cations monatomic ions cations retain their call as elements. The NH4+ ion, ammonium ion is named as if it were a metal ion because of its common flavourlike properties. Li+ lithium ion Na+ sodium ion Mg2+ magnesium ion Al3+ aluminium ion 1. 2. 2 Monatomic AnionsMonatomic anions are named using their names as elements and the suffix id e. C4- carbide N3- nitride O2- oxide H- hydride 1. 2. 3 Metals with Fixed oxidisation metrical composition The metals with fixed oxidation numbers are the IA and IIA, Aluminum and Zinc. All other metals have variable oxidation numbers. Note that no prefixes are used. NaCl atomic number 11 chloride Na2S Sodium sulfide AgBr silver bromide Al2O3 aluminum oxide 1. 2. 4 Metals with Variable Oxidation Numbers In a binary compound of a metal of this type with a nonmetal, the oxidation number of the metal must be indicated in the name. There are two methods of doing this, the classical system and the burgeon forth or Roman numeral system. 1. 2. 4. unsullied System This system can only be used for metals having two oxidation states. An ic ending is used for the metal with the highest oxidation state and an ous ending is used for the net. Also, the Latin name is used for iron (ferric and ferrous), copper (cupric and cuprous), tin (stannic and stannous) and lead (plumbic or plumb ous). The classical system does not indicate the actual oxidation state. 1. 2. 4. 2 contain System or Roman issue System The actual oxidation state is designated by a Roman act placed in parenthesis immediately following the name of the metal. This is useful especially if the metal has more than two oxidation states. Formula Classical System gunstock System CuCl Cuprous chloride copper(I) chloride CuCl2 Cupric chloride copper(II) chloride FeCl2 ferrous chloride iron(II) chloride FeCl3 ferric chloride iron(III) chloride 1. 3. Compounds Named Like Binary Compounds a few(prenominal) other compounds take an ide ending, like binary compounds. These include the following OH- hydroxide O22- bleach CN- cyanide NH2- amide I3- triiodide N3- azide 1. 4. Trivial Names Some common binary compounds are depute trivial names that have been appoint arbitrarily. These are universally used that they are allowed by the IUPAC rules of nomenclature. H2O water NH3 ammonia PH3 phosphine AsH3 arsine 1. 5. Binary Acids A binary compound composed of hydrogen with a more electronegative element can act as a binary acid in water solution. For acids of this types, the prefix hydro- is added, and then the ide ending is replaced by ic acid. HF hydroflouric acid HCl hydrochloric acid HBr hydrobromic acid HI hydroiodic acid 2. Ternary and Higher Compounds 2. 1 Oxyacids and salinitys Oxyacids are composed of a nonmetal with more than one oxidation state, on with hydrogen and oxygen. A salt of oxyacid is formed when one or more of the hydrogen ions of an acid is replaced by a cation. The prefix hypo-, is used to relate the lowest oxidation state of the nonmetal with the characteristic ending ous and the prefix per- is used to denote the highest oxidation state with the ending ic. For acids whose names end in ous, the corresponding salt ends with the suffix ite, and those whose names ends in ic, the name of the salt ends in ate. Acid Oxyanion Salt H2SO3 sulfurous acid SO32- sulfite Na2SO3 sodium sulfite H2SO4 sulfuric acid SO42- sulfate Fe2SO4 iron(II) sulfate HClO hypochlorous acid ClO- hypochlorite NaClO sodium hypochlorite HClO2 chlorous acid ClO2- chlorite KClO2 potassium chlorite HClO3 chloric acid ClO3- chlorate NaClO3 sodium chlorate HClO4 perchloric acid ClO4- perchlorate NaClO4 sodium perchlorate 2. 2 Salts of Polyprotic Acids These types of salts are formed when one or more hydrogen ions in polyprotic acids or acids with more than one replaceable H+ ion (e. g. , H2S, H3PO4, H2SO4) is/are replaced by metal ions. In naming, the word hydrogen is added to the name of the oxyanion. NaH2PO4 sodium dihydrogenphosphate Na2HPO4 disodium hydrogenphosphate Na3PO4 trisodium phosphate NaHS sodium hydrogensulfide EXERCISES 1. Name the following. a. FeI2___________________________________ b. I2___________________________________ c. FeCl3___________________________________ d. Fe2(SO4)3___________________________________ e. FeS_________________ __________________ f. NCl3___________________________________ g. H2CO3___________________________________ h. CaCO3___________________________________ i.Be2C___________________________________ j. SnSO4___________________________________ k. (NH4)2S___________________________________ l. N2O4___________________________________ 2. Write the correct chemical formula a. atomic number 56 chloride___________________ b. Stannous nitrate___________________ c. Stannic nitrate___________________ d. Aluminum carbide___________________ e. Magnesium phosphate___________________ f. Nitrogen dioxide___________________ g. Ammonium sulfate___________________ h. Barium carbonate___________________ i. Sodium carbonate___________________ j. Calcium hydrogen phosphate___________________ k. Disulfur dichloride___________________ 3. Complete the following table Formula Name as acid Formula of sodium Name of salt salt HNO3 HNO2 HBrO HBrO2 HBrO3 NaBrO3 HBrO4 4. Name the following a s binary compounds or as salts from the anions of polyprotic or oxo acids. a. NaIO___________________________________ b. K2HPO4___________________________________ c. Na2SO3___________________________________ d. KMnO4___________________________________ e.BaSO3___________________________________ f. FeSO4___________________________________ g. HClO3___________________________________ h. Na2SO4___________________________________ i. Fe(NO3)3___________________________________ j. Ca(ClO2)2___________________________________ 5. The spaces below represent portions of some of the main groups and periods of the periodic table. In the proper squares, write the correct formulas for the chlorides, oxides and sulfates of the elements of Groups 1, 2 and 3, respectively. Likewise, write the formulas of the compounds of sodium, calcium and aluminum with the elements of Groups 6 and 7. 2 of the squares have been completed as examples. completion Group 1 Group 2 Group 3 Group 6 Group 7 2 LiCl (Omi t sulfate) Li2O Li2SO4 3 Na2S CaS Al2S3 4 5 ExPERIMENT water supply OF HYDRATION Most solid chemical compounds will contain some water if they have been exposed to the atmosphere for any length of time.In most cases the water is present in very small amounts, and is mere adsorbed on the surface of the crystals. Other solid compounds contain larger amounts of water that is chemically flinch in the crystal. These compounds are usually ionic salts. The water that is present in these salts is called the water of hydration and is usually bound to the cations in the salt. In this experiment you will study some of the properties of hydrates. You will identify the hydrates in a group of compounds, observe the reversibility of the hydration reaction, and test some substances for efflorescence or deliquescence. Finally you will be asked to determine the amount of water lost by a sample of unfathomed hydrate on heating. From this amount, if given the formula or the submarine mass of the anhydrous sample, you will be able to calculate the formula of the hydrate itself. MATERIALS AND APPARATUS watch glass iron ring melting pot tongs test tubes iron stand triangular clay Bunsen burner melting pot desiccators PROCEDURE 1. Identification of provides. Place about 0. g of the compounds listed below in small, dry test tubes, one compound to a tube. Observe carefully the behavior of each compound when you heat it gently with a burner flame. If droplets of water condense on the cool upper walls of the test tube, this is evidence that the compound may be a hydrate. Note the nature and the color of the symmetry. Let the tube cool and try to dissolve the residue in a few cm3 of water, warming very gently if necessary. A true hydrate will tend to dissolve in water, producing a solution with a color very similar to that of the original hydrate. If the compound is a carbohydrate, it will give off water on h eating and will tend to char.The solution of the residue in water will often be caramel colored. plate chloride special K chloride Sodium tetraborate (borax) saccharose Potassium dichromate Barium chloride 2. Reversibility of Hydration. Gently heat a few crystals 0. 3 g, of furnish cobalt (II) chloride, CoCl2(6H2O, in an evaporating dish until the color change appears to be complete. Dissolve the residue in the evaporating dish in a few cm3 of water from your wash bottle. Heat the resulting solution to boiling (CAUTION ), and carefully boil it to dryness. Note any color changes. Put the evaporating dish on the lab bench and let it cool. 3. Deliquescence and skin rash.Place a few crystals of each of the compounds listed below on separate watch glasses and put them next to the dish of CoCl2 prepared in Part B. Depending upon their composition and the relative humidity (amount of moistures in air), the samples may gradually either lose water of hydration to, or pick up water from, t he air. They may also remain unaffected. all changes in crystal structure, color, or appearance of wetness should be noted. Observe the samples occasionally during the rest of the laboratory period. Since the changes tend to occur slowly, your instructor may have you compare your samples with some that were set out in the laboratory a day or two earlier. Na2CO3(10H2O (washing soda) CaCl2KAl(SO4)2(12H2O (alum) CuSO4(5H2O 4. Percent Water in a Hydrate. Clean a porcelain crucible and its cover with 6 M HNO3. Any stains that are not removed by this intercession will not interfere with this experiment. Rinse the crucible and cover with distilled water. Put the crucible with its cover slightly ajar on a clay triangle and heat with a burner flame, gently at first and then to redness for about 2 minutes. Allow the crucible and cover to cool, and then weigh them to 0. 001 g on an analytical balance. Handle the crucible with clean crucible tongs. Obtain a sample of unnamed hydrate from th e stockroom and place about a gram of sample in the crucible.Weigh the crucible, cover, and sample on the balance. Put the crucible on the clay triangle, with the cover in an off-center position to allow the circumvent of water vapor. Heat again gently at first and then strongly, keeping the bottom of the crucible at red heat for about 10 minutes. cracker bonbon the cover on the crucible and let it cool to room temperature. Weigh the cooled crucible along with its cover and contents. Examine the solid residue. Add water until the crucible is two thirds full and stir. Warm gently if the residue does not dissolve readily. Does the residue appear to be soluble in water? DATA AND OBSERVATIONS A. Identification of Hydrates Water appears pretense of residue Water soluble Hydrate Nickel chloride Potassium chloride Sodium tetraborate Sucrose Potassium dichromate Barium chloride B. Reversibility of Hydration tally your observations on CoCl2(6H2O. Is the deh ydration and hydration of CoCl2 reversible? C. Deliquescence and Efflorescence Observation Conclusion Na2CO3(10H2O CaCl2 KAl(SO4)2(12H2O (alum) CuSO4(5H2O D. Percent water in a Hydrate atomic pile of crucible and cover upsurge of crucible, cover, and solid hydrate Mass of crucible, cover, and residue Mass of solid hydrate Mass of residue Mass of water lost percent of water in the unknown hydrate Formula mass of anhydrous salt (if furnished) Number of moles of water per mole of unknown hydrate ExPERIMENT GASESThis experiment illustrates three of the common gas righteousnesss Boyles law, Charles and Gay-Lussacs law and whole meal flours law. Boyles law states that the volume, V, of a certain sum of an ideal gas is in return proportional to its pressure, P, at a given temperature and amount of gas. Charles and Gay-Lussacs law states that the volume of a gas is directly proportional to the implicit temperature, at a certain pressure and amount of g as. Grahams law describes that the velocity of an ideal gas is inversely proportional to the square root of its molar mass. The first two gas laws will be validated using plots of the properties involved. Grahams law will be determined by comparing the velocities of two sample gases. MATERIALS AND APPARATUS Glass spray 250 or 400-mL beaker Black cardboard syringe holder Iron stand prescript Thermometer Iron ring Graphing paper glycerol Wire gauze Concentrated HCl pattern clay Glass tubing