Why does the mixture bubble?
Start a little foamy volcano
Not every mixture produces bubbles
Add water to the soda. Water helps the soda particles disperse. Some of the soda dissolves.
But this does not cause violent bubbles. To get them in our experiment, you need to add another substance to the soda - vinegar.
Not everything we mix bubbles. First look at soda with water, and then compare with vinegar.
New gas appears
Vinegar contains acid. When its particles meet particles of soda, they combine in a new way. Other substances are obtained.
One of them is gas. It is called carbon dioxide. It collects in bubbles and comes out of the liquid. That's why the mixture sizzles!
Gas appears during this transformation. When the required soda or acid runs out, new bubbles will stop appearing.
Soap holds bubbles
Add a drop of soap. It helps to create thin films around the bubbles, like soap bubbles.
Now the bubbles don't burst so quickly. There are a lot of them nearby - it turns out to be foam! The gas in the bubbles is still created by baking soda and vinegar.
The foam rises and then settles: the bubbles burst. Our experience is similar to a small eruption, but a real volcano works differently.
For adults · discuss together
It's an on-screen experience. A real volcano works differently.
Before experience
Ask: “What do you think will happen?” Let the child check his guess first.
After the experience
What has changed? What remains the same? Where can you notice a similar phenomenon?
