Why is lemonade able to clean pennies?

While lemonade can clean pennies to a certain extent, it is not the most effective cleaning method. There are better and more efficient ways to clean pennies. Here's why lemonade has some cleaning effect on pennies:

Acidic Nature: Lemonade contains citric acid, which is a mild acid. This acidity can help dissolve the tarnish and dirt that accumulate on pennies over time. The acid reacts with the copper oxide layer on the surface of the pennies, breaking it down and removing it.

Abrasion: The pulp and small particles in lemonade can act as a mild abrasive when you rub the pennies with the lemonade solution. This gentle abrasive action helps to physically scrub away dirt and grime from the surface of the pennies.

Chemical Reaction: The copper in pennies reacts with the citric acid in lemonade, leading to a chemical reaction that results in the formation of copper citrate. This compound is soluble in water, which means it can be easily rinsed off, taking away the tarnish and dirt along with it.

However, it's important to note that lemonade alone may not be sufficient to remove heavy tarnish or dirt from pennies. For more effective cleaning, it's recommended to use specific cleaning methods designed for coins, such as soaking them in a mixture of baking soda and vinegar, followed by rinsing and drying them thoroughly.