In most conversations, “money laundering” refers to a white collar crime, but not here! We’re going to literally launder money … without illegal money transfers!
All jokes aside, we’re going to use vinegar to clean metal coins.
Here’s what you’ll need:
– a few old, dull pennies
– 1/4 cup white vinegar
– 1 teaspoon salt
– non-metal bowl
– paper towels
In your bowl, stir together the vinegar and salt.
Add up to five pennies to the bowl and slowly count to 10. Don’t use rare coins as the cleaning process can reduce the coins’ value for collectors.
Remove the pennies and rinse them in water. Set them aside to air dry.
Add another five pennies to the bowl and slowly count to 10.
Remove those pennies, and dry them on a paper towel without rinsing them in water.
After a minutes, compare the pennies that were rinsed in water with those that were dried on a paper towel.
How It Works:
Vinegar is an acid. When it reacts with the salt in the water, it removes the copper oxide from the surface of the pennies to make them clean again. The pennies that were rinsed in water will look like new. The pennies that were dried without rinsing will soon form malachite, a green-blue chemical on the surface.
Stay tuned for even more fun experiments on LabNotes!
These experiments are intended for inquiring young chemists and their adult supervisors. In all experiments, responsible adults should assist throughout to ensure proper safety precautions are followed. Eye goggles, gloves, etc. may be required.