Easy⏱ time30 min$ cost7
Reaction Volcano
Baking soda and vinegar erupt on cue while you measure how the ratio changes the blast.
Start building ↓
Result first
The build
Step 01
Build the cone
Shape a cone around the bottle on a tray.
Step 02
Charge the bottle
Add baking soda, a squirt of soap and colouring.
Step 03
Pour the vinegar
Add vinegar quickly and step back.
Step 04
Measure it
Catch and weigh the overflow to compare amounts.
Working Principle
Acidic vinegar reacts with basic baking soda to release carbon-dioxide gas; trapped by soap, it foams up and overflows as 'lava'.
The science behind it
A closer look
It is an acid–base reaction that produces a gas; measuring the foam is really measuring the CO₂ produced.
Take it further
Variables to test
- 1 Vary baking soda with fixed vinegar — where does it peak?
- 2 Warm vs cold vinegar — faster reaction?
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