A mixture happens when you combine two or more things without making a new chemical. Combining milk and chocolate syrup makes chocolate milk—something most everyone likes. Combining sugar and cinnamon hides the bitter taste of the cinnamon. You taste the sweetness of the sugar and the spicy flavor of the cinnamon. Chocolate milk and cinnamon and sugar are examples of good mixtures.
Some things, though, do not do well when combined or mixed. Milk and French fries should not be mixed. The two tastes do not go together and the milk makes the French fries soggy. We call this a mess. Some chemicals don’t mix well, either. When two chemicals don’t mix well or form a different chemical scientists call this a reaction.
Let’s see how a chemical reaction works…and make a mess.
THINGS YOU NEED
- Zip-lock sandwich bag
- Vinegar (white or cider)
- Baking soda
- Food coloring (color of your choice)
- Outdoor area or the bathtub
HERE IS WHAT YOU DO
- After you gather the materials you need for this experiment, go outdoors or into your bathroom
- Pour ¾ cup of vinegar into the sandwich bag
- Add two or three drops of food coloring to the vinegar
- Seal the bag securely and lay it aside
- Lay the tissue out flat and place 1 heaping tablespoon of baking soda in the center of the tissue
- Carefully fold the edges of the tissue to the center so the baking soda does not fall out
- Open one edge of the sandwich bag and carefully place the tissue in the vinegar
- Quickly and carefully re-seal the bag and lay it flat on the ground or the middle of the bathtub
- Stand back, watch the chemical reaction and be prepared for a mini-explosion
WHAT JUST HAPPENED
When baking soda reacts with the acid in the vinegar it begins to foam.
The foam is carbon dioxide gas being made.
The gas is released into the air.
When the amount of gas takes up all the space in the bag and needs more space, the pressure of the gas forces the bag open. When all the baking soda and acid in the vinegar has joined together, the foaming stops and gas is no longer made.
TRY THIS TOO
- Repeat the experiment using different amounts of vinegar and baking soda and different types of containers. What happens?
- Mix baking soda with another acid such as lemon or lime juice. What happens?
- Mix baking soda with water, milk and juice. What happens?
WHAT YOU LEARNED BY DOING THIS EXPERIMENT
- Not all things should be mixed together.
- When you mix two or more things together to make a new chemical this is called a reaction.
- Combining two or more things without making a new chemical is called a mixture.
- Baking soda and vinegar makes a fun explosion
- Carbon dioxide gas is a fast-acting gas formed when baking soda is mixed with acid.