2. Thursday, May 12 th : A Day Friday, May 13 th : B Day Agenda Check lab write-ups Lab discussion Lab: An Experiment in Alchemy: Copper to Silver to Gold - Lab will be due TODAY! Movie: Making Stuff: Smaller Next time: Chapter 7 Jeopardy Chapter 7 Test: Wed. 5-18/Thurs. 5-19

3. An Experiment in Alchemy: Copper to Silver to Gold One of the goals of ancient alchemists was to change base metals into gold. The purpose of this lab is to produce color changes in a copper token that will seem to turn copper into gold.

4. An Experiment in Alchemy: Copper to Silver to Gold First, you will clean copper pennies in a mixture of sodium chloride, NaCl, and vinegar. Next, you will turn the pennies to silver by adding them to a zinc/sodium hydroxide (NaOH) mixture in an evaporation dish on a hot plate. Finally, you will turn the silver pennies to gold by heating them in the bunsen burner flame.

5. Lab Hints An Experiment in Alchemy: Copper to Silver to Gold After cleaning the pennies in the sodium chloride/vinegar mixture, DO NOT touch them with your bare hands. The oils on your hands will interfere with the reaction. You will be using a hot plate to heat the zinc/sodium hydroxide mixture, NOT the bunsen burner.

6. An Experiment in Alchemy: Copper to Silver to Gold Safety Items Be extremely careful when heating the zinc/sodium hydroxide (NaOH) mixture! Sodium hydroxide is corrosive and will splatter if you heat it too aggressively! Do NOT allow the mixture to actively boil and use extreme caution when handling it. DO NOT breathe in the NaOH vapor when its on the hot plate!

7. An Experiment in Alchemy: Copper to Silver to Gold Safety Items You will be using bunsen burners so hair must be tied back. You must wear lab aprons (I know its hot) because you DO NOT want hot NaOH spilled in your lap!

8. The sodium chloride/vinegar mixture can be safely poured down the drain with water. DO NOT pour the zinc/sodium hydroxide solution down the drain. Pour most of the sodium hydroxide out into the waste beaker, rinse the zinc with distilled water, and pour the zinc in the filter funnel to be reused. An Experiment in Alchemy: Copper to Silver to Gold Disposal

9. An Experiment in Alchemy: Copper to Silver to Gold Use complete sentences to answer the questions. Make sure you have the proper units (labels) in your data table. We will NOT be doing the extension sections, so you DO NOT need to answer these. Make sure to update your table of contents. The lab will be due TODAY!

10. Movie: Making Stuff: Smaller This movie ties right into the nanotechnology work that is being done now at the University of Illinois that Joe Muskin talked to you about last class period… You DO NOT have to take notes on the movie – enjoy! Next time: Chapter 7 Jeopardy Chapter 7 Test: Wed. 5-18/ Thurs. 5-19