2ChemCatalystLong ago, people tried to turn ordinary things into gold. This pursuit was called alchemy and the people who engaged in alchemy were called alchemists.Do you think the alchemists were successful in turning things to gold? Explain your thinking.Unit 1 • Investigation I
3ChemCatalystLong ago, people tried to turn ordinary things into gold. This pursuit was called alchemy and the people who engaged in alchemy were called alchemists.Do you think with all the advances in technology that we can find a cheap method to turn things into gold?
4ActivityPurpose: In this activity you will be transforming a copper penny and discussing what happens.Safety Note: You must weat safety goggles at all times. DANGER! Sodium hydroxide will burn skin, eyes, and clothing.(cont.)Unit 1 • Investigation I
5The Big Question Can we turn a penny into gold? Unit 1 • Investigation I
6You will be able to:Follow a procedure using lab equipment and describe your observations.Unit 1 • Investigation I
7Materials Penny 2 tongs Hot plate Bunsen burner Striker Goggles Paper towels2 100 ml –beaker1 250 ml beaker half filled with waterLab glovesChemicals:Zinc filings (just enough to cover the bottom of the 100 ml beaker (10 g)25 ml of 3M sodium HydroxideCold tap water
8Steps to make the NAOH solution Must be 3 MFor 1 M you would use 40 g of NaOH to make a 1L solutionPut 40 g in about .8 liters, dissolve, then fill to 1 liter markTriple amount of NaOH to get 3 MSince we need only about 0.5 L, cut total in ½Thus mix 60 g of NaOH into 400 ml of water then fill to 500 ml level
9Lab Jobs to be divided up Safety Czar:Make sure everybody is wearing gogglesGloves are being used where appropriateHair and sleeves have been addressed by allTeam members are keeping safe distanceIn charge of Group’s actionsPenny MoverUses tongs to place penny into Sodium hydroxide solution and takes penny out when finishedPlaces penny into waterHot Plate specialistTurns on and monitors Solution on Hotplate, makes sure beaker is in middleRecords the initial and final amounts of solution in beakerTurns off hot plate when section is doneSodium Hydroxide HolderUses tongs to hold Sodium Solution Beaker as Penny Mover does his tasksIn charge of getting a beaker of sodium hydroxide solution from fume hood at start of class and returning cool beaker at end of periodBlocker/Flame Keeper/Spill PatrolMakes sure that no one bumps Sodium Hydroxide holder as they walk with solution beakerLights and monitors Bunsen BurnerTurns off Gas at end of lab
11PROCEDURE For silvering the penny For turning penny into gold Place zinc filling in beaker, covering bottomCarefully add 20 ml of NAOH solution to beakerPlace on hot plate and set to 4, if liquid boils, turn downUse tongs to place penny in beaker, with helpOnce it turns completely silver remove with helpPlace penny in 250ml beaker to cool and rinseSet up Bunsen burnerLight burner with striker/matchAdjust flame using metal collar (blue is hottest)Use tongs to place silver penny into flameHold penny in flame only until it changes color, no longerPlace in 250ml beaker to cool down
13The running of the Penny lab This lab will be done under the direct supervision of the teacher, because of the dangers involvedAny action taken by a student that I deem detrimental to the class will be dealt with swiftly and harshly!
14Steps to the labStep 1 is prep and safety (goggles!, review safety tips)Step 2: Turn the penny silver by placing it into a heated solution that contains Sodium Hydroxide and ZincStep 3: Turn Penny into gold by putting it into the flame of a Bunsen burnerWhen you are not active in the lab, you should be observing others and answering questions
15Clean up Any spills of Sodium Hydroxide must be immediately addressed Use paper towels to stop flow (make sure you are wearing goggles and gloves)Turn off hot plates once you are done with them, BEFORE you go on to Bunsen BurnersTurn off gas to burners after you are completed with section
16Response to questions Get out the composition book Add any other observations from the class to your own if you believe they improve what you have written. Note who said what
18Question 1 Describe what you observed during the experiment. Label and describe the materials/devices used, how they were set up for use, and what actions occurred.After the step took place, indicate the general results with as much detail as possible
19Question 2What do you think happened to turn the penny silver?
20Question 3What do you think happened to turn the penny gold?
21Question 3 Making SenseDo you think you made real gold? Explain your response.
22Question 4 Making senseHow could you find out if you did make real gold?
23At the end of class Picture If you do not want your penny, I will keep it
24Which is the main focus of our next section Discussion of mass and volume requires one to understand what matter isWhich is the main focus of our next section