How Does a ‘Volcano’ Erupt and What Makes It Powerful?

A volcano erupts when pressure builds up inside it. Imagine a soda bottle that’s been shaken and capped, when you open it, the soda explodes out because of all the bubbles. A volcano is like a giant soda bottle full of hot rock and gas. When the pressure becomes too much, poof! The lava, ash, and smoke shoot out into the air.