Today’s vocab word of the day is acidic! Acids are sour substances. Their pH value is lower than 7. An example of acidic substance is vinegar, which we will be using in our experiment.
Have you have seen an older penny that is no longer shiny? Well, today you can learn how to make your pennies shiny again!
A couple older, no longer shiny, pennies
Vinegar (1/4th cup)
Pour the vinegar into the non-metal bowl and also add the teaspoon of salt. Make sure to stir it!
Put a few, around 5, pennies in the bowl and wait about 10 seconds
Take the pennies out of the vinegar and wash them in water. They should be shiny!
Why does this work?
The mixture of vinegar and salt creates a weak acid, that will react with the dull, outer copper oxide layer of the pennies! The acid removes this layer when you rinse the pennies underwater. However, if you leave the pennies coated in the acidic substance without rinsing them, it actually makes it easier for your pennies to become dull again.