Igneous Rocks

What type of rocks form when lava cools on Earth's surface?

• Intrusive

• Extrusive

• Course-grained

• Sedimentary

Rocks are made out of minerals.

• True
• False

Which igneous rock has no visible crystals?

• gabbro

• granite

• obsidian

Why does pumice, an igneous rock, have holes?

• It forms from gas-rich lava.

• It forms deep beneath Earth's surface.

• It forms from magma that is rich in silica.

Intrusive igneous rocks are made of

• small particles of ash.

• mostly volcanic glass.

• large, interlocking crystals.

Where is magma found?

• inside Earth

• on the surface of the Earth

Where is lava found?

• inside Earth

• on the surface of the Earth

How do extrusive igneous rocks form?

• from lava that erupted onto Earth's surface

• from magma that hardened beneath Earth's surface

How do intrusive igneous rocks form?

• from lava that erupted onto Earth's surface

• from magma that hardened beneath Earth's surface

Fine-grained igneous rocks with small crystals formed from

• rapidly cooling lava

• slowly cooling magma