How to Make a Soda Bottle Volcano

Co-authored by Bess Ruff, MA

Last Updated: November 18, 2022 Approved

Making a soda-bottle volcano is a classic science experiment that doubles as a great excuse to make an explosive mess. There are multiple combinations of materials that will lead to a fun explosion. Two of the classic soda-bottle volcanos are made with soda and Mentos candy mints(which can produce eruptions of up to 18 feet if done correctly) or a combination of baking soda and vinegar. Gathering a few household items can lead to a fun afternoon of volcanic explosions in the backyard.

Method 1

Method 1 of 3:

Designing the Volcano

1
Find a base for your volcano. This can be a plastic cutting board, a piece of scrap wood, or any other sturdy, flat surface that can be spared for a while. Avoid cardboard, as it will likely be too flimsy to support your project.
- 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.
2
Attach a full, unopened, 2-liter soda bottle to the base. Since you will build the volcano around the bottle, be sure to place it in the center of the base. How you attach it will depend on what your base is. If it’s a kitchen cutting board, place a lump of clay or Play-Doh on the board and lightly crush the bottle into it for a loose hold. If you’re using scrap wood, use a plastic/wood adhesive.
- 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.
Advertisement
3
Build the volcano around the bottle. For a textured look, shape some chicken wire into a lumpy, mountainous cone around the bottle. Cover the chicken wire with papier-mâché. An alternative to paper-mâché is to sculpt some clay around the bottle. For a more solid look, shape green, gray, or brown play-dough or clay around the bottle.^{[1]
X
Research source}
- 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!
4
Paint the volcano. After you have let the paper-mâché dry, paint it with acrylic paint (which will also help seal out moisture). Use shades of brown and orange around the top and add some green to look like grass.
- You may even want to press pebbles, dirt, and moss into the surface to give it a more natural appearance.

Method 2

Method 2 of 3:

Using the Soda and Mentos Method

1
Gather the necessary materials. To make this type of volcano, you will need a two-liter bottle of cola, a roll of Mentos brand candy mints, and a large open area. Diet cola appears to work better than regular soda (it’s also less sticky than regular soda). Sodas with caramel color look more like ‘lava’ when they erupt as compared to clear lemon-lime sodas.^{[2]
X
Research source}
- This experiment is best done outside, but if you must be inside, lay down a large plastic tarp first.
2
Position the volcano in a large, outdoor area and open the soda bottle. Avoid doing this experiment inside, as it will create a huge, sticky mess. Make sure your outdoor area is also uncovered since the soda can erupt quite high. Remove the cap from the soda bottle.
- Warn any spectators to stand back.
3
Prepare a whole roll of Mentos to drop into the bottle. When Mentos come in contact with the soda, a reaction occurs that causes the carbon dioxide gas in the soda to push the liquid out of the bottle. The more Mentos you drop in all at once, the greater the eruption; however, this can be difficult.^{[3]
X
Research source} There are a few different ways to deliver the Mentos into the bottle.
- 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.
4
Release the Mentos into the bottle and run. Getting all the Mentos to fall in the bottle simultaneously is quite hard. If done incorrectly, the volcano will only rise a few inches or so. Practice getting the Mentos to drop simultaneously a few times before wasting your bottle of soda. Once the Mentos drop into the bottle, run a few feet away to observe the eruption!
- 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.

Method 3

Method 3 of 3:

Using the Baking Soda and Vinegar Method

1
Gather the necessary materials. For this volcano, you will need 400 milliliters (13.5 fl oz) of vinegar, 200 mL of water, a squirt of dishwashing liquid, a large spoonful of baking soda, an empty 2-liter soda bottle, and red food coloring.^{[5]
X
Research source}
- 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.
2
Combine vinegar, water, and a squirt of dishwashing liquid. Add the ingredients to the volcano. The liquid soap breaks the surface tension of water, therefore creating a larger eruption.^{[6]
X
Research source}
3
Place the volcano on a plastic-covered table or over a linoleum floor. This method won’t make as big a mess as the Mentos method, but you definitely don’t want to have to scrub the results out of a carpet or rug.
- If the weather is agreeable, place the volcano outside.
4
Add a spoonful of baking soda to the mixture. The baking soda will react with the vinegar mixture and cause your volcano to erupt! If you want a larger explosion increase the amount of vinegar and baking soda used.^{[7]
X
Research source}

Community Q&A

Question

What is the law or theory regarding the experiment of the soda volcano?

Community Answer

When you add vinegar to bicarbonate of soda, a chemical reaction occurs – the result is "carbonic acid." This is an unstable substance – you can tell from all the fizzing! The mixture instantly separates into a gas and a liquid, producing carbon dioxide and water.
Question

Can I use water to make it erupt?

Community Answer

Plain water will not react with the bicarbonate. The main ingredients are the vinegar and bicarbonate.
Question

Why do volcanoes burst?

Community Answer

Pressure builds over great periods of time, and eventually they erupt and release all the pressure at once.

Warnings

If you drink soda and then eat Mentos, do not worry at all; the acid in your mouth and stomach will stop it from reacting with the soda in your belly.

⧼thumbs_response⧽
Helpful 0 Not Helpful 0
Don't use a 3- or 1-liter bottle, as the neck-to volume-ratio is too large. A 3-liter bottle results in about a 6-inch tall fountain and a 1-liter bottle it will just foam over the top.

⧼thumbs_response⧽
Helpful 0 Not Helpful 0
Stay away from the immediate area after starting the volcano. It will get messy.

⧼thumbs_response⧽
Helpful 0 Not Helpful 0

Things You'll Need

Volcano and Base

Scrap wood or cutting board for a base
Play dough or clay
Alternatively, papier-mâché
- Chicken wire
- Strips of paper
- White craft glue
- Water
- Acrylic paint