8th Grade Science Fair Projects

Engaging 8th grade science fair projects can be fun for the whole family. Science relies on pH levels for testing many different things. But, if you don't have the pH paper test strips, you can actually make them yourself! This can be a great science fair project that is sure to impress everyone!

Red cabbage contains a coloring element called flavin (an anthocyanin) Solutions that are high in acidity will turn anthocyanin a red colour. Solutions that have what is considered to be a neutral acidity will have a purplish colour and basic solutions will be a green or yellow color. Because of this, one can easily measure the pH level in a substance when red cabbage leaves are dipped in the solution. The color of the leaves will change in response to changes in its hydrogen ion concentration. Below is a chart showing what pH levels will show which colors.

The different levels of pH will result in different colors: pH level of two will be red, pH level of four will be purple, pH level of six will be violet, pH level of eight will be blue, pH level of ten will be blue or green, and a pH level of twelve will be green or yellow.

Materials Needed:

• Red cabbage
  
• A sharp knife for chopping
  
• Boiling water
  
• Paper that can filter such as coffee filters
  
• A glass container (a beaker will work well)
  
• Six 250ml small glass containers
  
• Household ammonia
  
• Baking soda
  
• Washing soda
  
• Lemon juice
  
• Vinegar
  
• Cream of tartar
  
• Antacids
  
• Seltzer water
  
• Muriatic acid or masonry's cleaner
  
• Lye

What to do:
1.) Using the knife, break the cabbage into enough small pieces to equal two cups of cabbage. Place the cabbage in a large glass container and pour boiling water over top. Leave in water for approximately ten minutes to allow the colour to drain out of the leaves. You can also put the cabbage and boiling water in a blender.
2.) Take out everything but the liquid so you are left with a reddish or purplish coloured liquid. This liquid is approximately pH 7.
3.) Pour a little bit of the liquid into each of the small glass containers.
4.) Add different household ingredients to your colour indicator to achieve different colour results. Make sure to use different containers for each ingredient - you don't want to mix ingredients that shouldn't be combined!

Some important notes to keep in mind while doing this project:

• Make sure you wear the appropriate goggles and safety gloves when doing this project as it involves strong acids and bases
  
• Everything used in this project is perfectly safe to be washed down the drain.
  
• It's possible to create your own pH paper strips by soaking a coffee filter into the normal pH cabbage juice indicator. Hang the strips with a string or a clothespin to allow them to dry.

As you can see, as 8th grade science projects go, this one will take a little work. But, the payoff is equally rewarding.

Note: See the Disclaimer before starting this project.