Alloy Demonstration

This is the classic “golden penny” alchemy experiment.

Sodium Hydroxide SDS

3M solution of Sodium Hydroxide

(make 333 ml) use 40g

granulated zinc

copper penny

From Szczepankiewicz:

  • Step A. Granular zinc dissolves in NaOH solution, forming a zincate anion, [z~(oH)~]”.
  • Step B. Zincate ion becomes reduced to metallic zinc on the surface of the copper penny.
  • Step C. Zinc and copper, when heated in the Bunsen burner flame, form brass.



Szczepankiewicz, Steven H., Joseph F. Bieron, and Mariusz Kozik. “The “Golden Penny” Demonstration: An Explanation of the Old Experiment and the Rational Design of the New and Simpler Demonstration.” Journal of Chemical Education 72.5 (1995): 386. Journal of Chemical Education. ASC Publications. Web. 27 Jan. 2016. <>.

Muhammad, Mir. “Making Solutions.” Home Science Tools. N.p., n.d. Web. 27 Jan. 2016. <>.