Inside a Volcano

Question 1

Sam sees a model of a volcano. The underground pool of hot, melted rock is called magma. When the volcano erupts, the same hot melted rock flows out and is called lava. Which sentence correctly describes this change?

Accepted Answer

Magma is the hot melted rock deep inside the Earth, and when it reaches the surface it is called lava.

Answer

Magma and lava are two different kinds of rock; magma stays underground while lava stays on the surface.

Answer

Lava is the solid rock that forms underground, and magma is the liquid that comes out during an eruption.

Answer

Magma turns into ash before it becomes lava, so they are not the same material.

Question 2

When a volcano erupts, the hot melted rock that comes out of the vent is called lava. Which statement best explains why we use the word lava instead of magma for that molten rock?

Accepted Answer

Because the melted rock has traveled from the underground magma chamber to the surface, it is the same material but is now called lava.

Answer

Because lava is a completely different kind of rock that forms only when the earth’s surface cools.

Answer

Because magma changes its chemical composition when it erupts, so the new material is called lava.

Answer

Because lava is the name we give to any hot liquid, even water, that comes out of a volcano.

Question 3

A cut‑away drawing of a volcano shows three different parts: a big underground space, a thin tube that goes up through the rock, and a bowl‑shaped opening at the top. Which choice correctly names each part?

Accepted Answer

Magma chamber = big underground space, vent = thin tube, crater = bowl‑shaped opening at the top

Answer

Magma chamber = bowl‑shaped opening at the top, vent = big underground space, crater = thin tube

Answer

Magma chamber = thin tube, vent = bowl‑shaped opening at the top, crater = big underground space

Answer

Magma chamber = big underground space, vent = bowl‑shaped opening at the top, crater = thin tube

Try three questions

Sam sees a model of a volcano. The underground pool of hot, melted rock is called magma. When the volcano erupts, the same hot melted rock flows out and is called lava. Which sentence correctly describes this change?

When a volcano erupts, the hot melted rock that comes out of the vent is called lava. Which statement best explains why we use the word lava instead of magma for that molten rock?

A cut‑away drawing of a volcano shows three different parts: a big underground space, a thin tube that goes up through the rock, and a bowl‑shaped opening at the top. Which choice correctly names each part?

Keep going on this shelf