If you’re working with scrap material, consider decorating the base to look like a flat landscape. You may want to paint it, cover it with moss, apply green felt to indicate grass, attach miniature trees, etc.
A caramel-colored soda will probably look the most like lava when your volcano erupts, so avoid clear drinks. Both diet and regular soda work for this experiment, but diet soda erupts higher. If gluing the bottle, let the bottle reach room temperature. A cold, sweating soda bottle will never glue properly. Avoid using hot glue, which might melt the bottle and make a mess. If you’re doing a vinegar and baking soda volcano, you will attach an empty bottle to the board.
Avoid covering the cap of the bottle or you won’t be able to activate the volcano. Ensure you have access to the opening so you can add Mentos or baking soda for the eruption!
You may even want to press pebbles, dirt, and moss into the surface to give it a more natural appearance.
This experiment is best done outside, but if you must be inside, lay down a large plastic tarp first.
Warn any spectators to stand back.
Method 1: Make a paper tube with the same width as the bottle neck. It should be long enough to fit the number of Mentos you want to put inside. Place an index card over the bottle mouth, place the tube over the hole, and fill it with Mentos. When you are ready to erupt, you will slide the card out, releasing the Mentos into the bottle. [4] X Research source Method 2: Loosely scotch tape the entire roll of Mentos together. When it’s time, you will drop the taped chain directly into the open bottle. Method 3: Insert into the bottle a funnel with a mouth that is wide enough to allow the Mentos to pass, but small enough to fit inside the neck of the bottle. You will drop the Mentos through the funnel and remove the funnel once the Mentos are in the bottle.
If using the paper tube method, remove the card holding the Mentos in place and let them all slide into the bottle at one time. If using the tape method, simply drop the piece of taped-together Mentos into the mouth of the bottle. If using the funnel, drop all the Mentos into the funnel at the same time. Remove the funnel once they’re all in and run back.
Do a little experimentation to find the proper amounts of each material to get the size of eruption you want. Use red-wine vinegar for the best lava coloring. Alternatively, you can also add red or orange food coloring to white vinegar. You can use a smaller plastic bottle, but will have to adjust the ingredients accordingly.
If the weather is agreeable, place the volcano outside.
