How Can Rocks Be Classified?

What is a rock? Choose the best scientific definition.

• A huge pebble that came out of a volcano..

• A piece of a mountain which can be of many color.

• A piece of very hard land which will hurt you if it hits you.

• A natural solid made of one or more minerals.

Which is not a type of rock?

• sedimentary

• igneous

• metamorphic

• sandy

What there must be before an igneous rock might form?

• The ice age.

• A forest fire.

• A volcano.

• An earthquake.

Explain when an igneous rock forms.

Where do igneous rocks form? Check all that applies.

• At the bottom of the sea.

• Deep inside Earth.

• On the mountains.

• On the Earth surface near a volcano.

What happens when magma cools slowly beneath Earth's surface?

• Large mineral crystals form.

• Small mineral crystals form.

• No mineral crystals form.

• Rocks do not have time to form.

What happens when magma cools quickly on the Earth's surface?

• Large mineral crystals form.

• Small mineral crystals form.

• No mineral crystals form.

• Rocks do not have time to form.

This is a mahogany obsidian rock. Tell wether it cooled beneath Earth's surface or above Earth's surface. Explain how you can tell.

This is a dolerite rock. Tell if it cooled quickly or slowly. Explain how you can tell.

What do you need to form a sedimentary rock?

• Pressure.

• Air.

• Water.

• Heath.