- Baking soda
- Measuring cup
- Scrub brush
- Olive oil
- Lemon juice
- Small bowls
- Gather all of your materials in one place. Every good scientist needs a work station. Make sure yours is in a well lit place with a flat surface like a table or counter.
- Get your first cleaner ready. This one is simple and easy! Just pour a bit of baking soda in a small bowl.
- Your second cleaner will actually require some mixing. Add one cup of vinegar and one cup of water in the second small bowl.
- For your third cleaner, mix one cup of olive oil and half a cup lemon juice in another small bowl.
- Your second and third cleaners have a lot of acid in them. There are some surfaces, like marble, that can actually be damaged by acidic cleaners. Ask an adult for help in identifying surfaces that are okay to test. Furniture made out of wood (tables, chairs, etc.) are great places to start.
- Think about what you know about cleaning. You've probably noticed how water does a great job at cleaning things. Do you think your homemade mixtures can do a better job?
- Write down your best guess in your notebook. Scientists call this type of guess a hypothesis.
- Time to clean! Use a sponge to scrub half of a sink with your first cleaner, the baking soda.
- Use a different sponge to scrub the other half of the sink with water.
- What happens? Is one side cleaner than the other side? Record your observations in your notebook.
- Try your second experiment. Scrub half of the bathtub with your second cleaning solution and the other half with water.
- Write down your observations again.
- For your last experiment, you'll work on wooden furniture. Rub half of a dusty piece of furniture with your third cleaner and the other half with water.
- What works better this time? Make sure you record what happens in your notebook.
- Take a look at your results. Is there a clear winner in the battle of homemade cleaners versus water?
Your homemade cleaner should work much better than water.
It all comes down to friction and chemistry! Your homemade cleaner worked so well because of physical and chemical changes that occurred between the solutions and the surfaces. What does that mean? Well, the basic facts are that when you add certain chemicals to certain messes, cleaning becomes a lot easier.
Let's look at your first experiment with baking soda and a dirty sink. Baking soda is an abrasive, which just means that it's good at grinding and polishing other substances. Another word for this grinding and polishing would be friction. Friction, in this case, encourages the dirt and grime on the sink to come off.
Your other two experiments have more to do with chemistry than friction. The chemicals in those cleaners, specifically the vinegar and lemon juice, had a lot of acid in them. Acid has a "buddy" called alkaline. When acid substances like your cleaner come into contact with alkaline substances like soap scum on bath tubs and dust on furniture, it causes a chemical change that makes it easier for you to wipe the surfaces clean.
On the other hand, water is neither an abrasive or an acid. Now it makes sense why scrubbing with water didn't really do much. Friction and chemistry were on the side of your homemade cleaners, not the water -- and that turned out to make all the difference.
Every time you use your homemade cleaners, science happens! Keep guessing and testing new ways to use science as you clean. What liquid would clean a mirror the best? What about a carpet? Scientists never stop experimenting and learning, and neither should you.