In this Mystery, students meet the alchemists, a historic group that used “potions” to try to transform materials. In the activity, students test what substances change the appearance of copper.
DISCUSS (1 of 2):
Do you think there could really be a potion that does something amazing or valuable? (Do you think there are really liquids or mixtures that can transform things?) Why or why not?
DISCUSS (2 of 2):
If you could make a potion, what would you want it to do?
GET A SUPPLY:
Everyone get 1 dull, brown penny. Then:
Suppose you wanted to make this dull brown penny bright and shiny. Can you think of any liquids in your house that might do that?
Why do you think those liquids might work?
Do you think oxygen turns the penny dark brown all the way through, or just on the surface? How could you figure it out?
How could you figure out which of these three ideas is true?
You've completed the Exploration & Activity!
Learn more about the alchemists and how their work laid the foundation for the science of chemistry with these readings:
“Can You Turn Iron into Gold?” from Wonderopolis, a website dedicated to curiosity and imagination, created by the National Center for Families Learning.
From Alchemy to Chemistry from Newsela, a free service for teachers. (Reading includes comprehension questions and can be adjusted for reading level.)
Try this experiment with a US penny made after 1982. These coins have a center made of zinc, a silvery metal that reacts with vinegar and salt.
In our experiment, the center of the penny dissolved leaving behind a thin shell of copper. What happened in your experiment?
Watch this time-lapse video, then discuss:
To find out more about what happens to rust and tarnish in vinegar, watch the next Mystery, "Could you transform something worthless into gold?"