2.The beaker at your lab station contains a concentrated solution of zinc chloride mixed with solid zinc. Zinc chloride is corrosive and can damage your skin. If you spill any on yourself during the lab, immediately wash your hands and notify your instructor. Goggles and aprons at all times! 3.Cover the ZnCl2beaker with a watch glass and place it on a hot plate. Gently heat the solution on medium until it starts to bubble, then lower the heat to continue gentle bubbling. Do not allow the solution to bubble vigorously or become heated to dryness. 4.Using crucible tongs, carefully lower your other two pennies into the solution, placing them on top of the solid zinc on the bottom of the beaker. Put the watch glass back on the beaker. 5.Heat the pennies for 3 to 5 minutes, observing for a change in their appearance. 6.Turn off the hot plate. Using crucible tongs, remove your pennies from the beaker, rinse them under running tap water, and dry them with a paper towel. Set one coin aside for later comparison. 7.Brieflyheat the other treated coin in the outer cone of a Bunsen burner flame. Heat until you see a color change, then REMOVE from the flame. Do not overheat. 8.Immediately rinse this heated coin under tap water, then gently dry with a paper towel. 9.In your data table, record observations of all 3 coins. Label each coin with an appropriate description. 10.Tape both treated coins into your data table, next to the control. 11.Wash your hands. Analysis: Analysis questions will be distributed in class. You must being three (3) pre-1982 pennies to class to complete this lab. The older the better…1970s pennies bring good results!
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