Baking soda and vinegar volcano
Recommended age: 6+. Adult supervision required! When baking soda meets vinegar, a fizzing gas forms and erupts from your homemade volcano as colourful, soapy foam — many children's very first chemistry experience.
Chemicals
- 3 tbsp baking soda
- 200 ml household vinegar (10%)
- 1 tbsp dish soap (this makes the foam thick and long-lasting) — this makes the foam thick and long-lasting
- pc red food colouring (a few drops, optional) — a few drops, optional
Procedure
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Put on your goggles! Vinegar stings the eyes, so nobody leans over the volcano during an eruption. An adult supervises throughout, and drinking the foam is forbidden.
Safety! -
Stand the bottle in the middle of the tray and build a volcano cone around it from clay or foil — the bottle mouth is the crater.
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Spoon 3 tablespoons of baking soda into the bottle. A funnel rolled from paper makes it easier to hit the opening.
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In the jug, mix the vinegar with the dish soap and a few drops of food colouring.
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Make a prediction: what will the volcano do, and how high will the foam get? Say it out loud before you pour!
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Pour the vinegar mixture into the bottle in one confident motion, then take a step back.
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Watch the eruption! Describe what you see and hear — is it fizzing, hissing, is the lava flowing?
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No need to start over for a refill: add another spoonful of baking soda and pour in more vinegar. Test what makes a bigger eruption — more soda or more vinegar?
Technique -
At the end, pour the leftovers down the drain with plenty of water, wipe the tray and wash your hands.
Apparatus
- 1× small plastic bottle — 0,5 l
- 1× deep tray or baking pan
- 1× modelling clay or aluminium foil for the cone
- 1× tablespoon
- 1× small jug for the vinegar
Frequently asked questions
- Why does it work?
- Vinegar is acidic, baking soda is basic. When they meet, a chemical reaction produces carbon dioxide gas. The dish soap traps the many tiny gas bubbles into a lasting foam, which pushes its way out of the bottle and 'erupts' like lava.
- Why does my volcano not erupt high enough?
- It comes down to three things: use fresh baking soda, pour the vinegar quickly in one go, and use a narrow-necked bottle — the smaller the opening, the higher the foam shoots.
- Can you eat the foam?
- No. Although every ingredient comes from the kitchen, it contains dish soap, which can cause nausea. This experiment is for the eyes, not the mouth.
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Every version of this image is kept. Nothing here was photographed in a lab — the illustrations are generated on ATAILA hardware, and when the models or the prompt improve we regenerate and keep the old one so the difference is visible.