Volcanoes have a secret!

Some pour out slow and calm. Some go BANG. Why?

2

Hot melted rock is full of fizzy gas bubbles.

melted rock gas bubbles
3

The gas always wants to get OUT — just like a shaken soda.

4

Tap to shake it — wake the bubbles up!

Tap — see the bubbles get busy.

5

This rock is thick and gluey. Will it OOZE or POP?

Tap your guess!