Igneous Rock and Volcanoes

Which type of rock forms when molten material cools and hardens inside Earth?

• an igneous rock

• an extrusive rock

• a rock with fine texture

• a rock with small crystals

Which two materials form igneous rocks upon cooling?

• lava and crystals

• magma and lava

• crystals and intrusive rocks

• intrusive rocks and sediment from rocks

How are extrusive rocks formed?

• magma gets trapped inside Earth and cools to rock

• volcanoes apply force to solid rocks and eject them

• magma gets forced to Earth's surface and cools to rock

• volcanoes trap lava inside Earth, where it cools to rock

Which phrase describes a feature of igneous rocks that cool quickly during formation?

• small crystals

• coarse surfaces

• found beneath Earth's surface

• exposed after erosion occurs

Which trait is common to rocks formed from magma trapped inside a volcano?

• less dense

• fine crystals

• coarse texture

• quickly cooled

How do intrusive rocks form?

• lava cools slowly outside a volcano

• magma cools slowly inside a volcano

• molten material is cooled quickly by water

• magma is ejected into the air and cools slowly

Which two features of igneous rocks are determined by their cooling rate?

• color and shininess

• shininess and hardness

• hardness and crystal size

• crystal size and rock texture

How are rocks that cooled within magma chambers found on Earth's surface today?

• they are pushed up by magma under Earth's surface

• they are revealed by erosion of Earth's surface over time

• they are pushed to Earth's surface because of their larger size

• they are revealed at Earth's surface due to their low density

An igneous rock is found on the ground and has no identifiable crystals. What is the most likely origin of this rock?

• molten material that cooled slowly

• molten material that cooled quickly

• rock that was eroded by surrounding rocks

• rock that was exposed to extreme pressure

Which property is used to identify the origin of an igneous rock?

• color

• density

• hardness

• crystal size