Imagine a bottle of cola. What happens when you shake the bottle and open it? The drink will explode out of the bottle. This is because the bubbles in the drink are made of gas. when you shake the bottle, There is more pressure. When you open the bottle, the gas comes out very fast.The same thing happens when a volcano erupts. Earth is very hot under the surface. it's so hot that the rock is liquid. This liquid rock is called magma. The temperature of magma is very high, between 700 and 1300. Magma forms bis caves inside Earth. They are called chambers. when pieces of rock fall into the magma they make gas. When the pressure of the gas is very high, the gas and the magma come up through a hole. The hole is called a crater. We often see ash clouds coming out from the crater before an eruption. When magma comes out of the crater, it's called lava. when lava gets cold, it becomes stone
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