Experimenting with vinegar and baking soda to release carbon dioxide gas provides the foundation for many junior science fair projects. The noticeable reaction that occurs when you combine white vinegar with sodium bicarbonate makes it a fun way for elementary school kids to learn about chemical reactions and carbon dioxide, one of the most common molecules on earth. From volcanoes to balloons, help your students with their baking soda and vinegar science projects.
This classic science fair project imitates an erupting volcano with a baking soda and vinegar reaction making the volcano's "lava." Use modeling clap to shape a hollow volcano around an empty plastic soda bottle. Paint and decorate the clay volcano as desired. Put a few drops of red liquid food coloring into the bottle and fill it almost to the top with white vinegar. When you're ready to show spectators an "eruption," pour a few tablespoons of baking soda into the soda bottle. The "lava" will bubble up and flow over the sides of your clay volcano, so make sure you place newspaper or a towel beneath your project.
Inflate a balloon with carbon dioxide to demonstrate how chemical reactions produce gas molecules. Hypothesize that combining vinegar and baking soda will release enough carbon dioxide to inflate a balloon. Start with an empty plastic bottle that can hold six to eight ounces of liquid. Fill the bottle with vinegar. Take a deflated balloon and fill it almost entirely with baking soda. Stretch the end of the balloon over the mouth of the bottle. When you're ready to cause a reaction and inflate the balloon, lift the hanging end of the balloon so the baking soda falls into the vinegar. Watch the balloon inflate, carefully remove it from the bottle and tie the end to store the carbon dioxide.
All rockets are launched by a combustion of chemicals. Students' science project can investigate how best to launch a miniature "rocket" with a combustion of baking soda and vinegar. Decorate an empty plastic film canister to look like a rocket. Place 1 teaspoon of baking soda mixed with 1/8 of a teaspoon of water into the depression of the canister lid. Fill the canister body with vinegar, quickly snap on the lid and place it on the ground. A chemical reaction should occur, causing the lid to pop off and the "rocket" to fly into the air. Measure how high the rocket flies and record it in a notebook. Try the experiment several times using different amounts of baking soda and vinegar to determine the optimum ratio for a high launch.
Use your project to demonstrate how carbon dioxide works when released in water. Fill a beaker halfway with water. Add 3 tablespoons of baking soda to the water and slowly pour vinegar into the water until it begins to bubble. As you pour the vinegar, add a handful of raisins to the vinegar. Carbon dioxide bubbles will attach themselves to the raisins, causing them to float to the top of the beaker. As the raisins meet the surface, the bubbles will break and the raisins will sink toward the bottom of the jar before the whole process repeats. The chemical reaction creates the illusion that the raisins are "dancing."