Rhyolite Characteristics and Properties

This video from MooMooMath and Science explores the properties of the igneous rock rhyolite. Rhyolite is light in color, classified as felsic, and contains over 70% silica. It is an extrusive rock formed from rapid cooling lava, resulting in small, often invisible crystals. Rhyolite is produced by violent volcanic eruptions and has a density between 2.4 and 2.6 grams per cubic centimeter. Its texture is fine-grained and aphanitic, meaning the crystals are not visible to the naked eye. The video concludes with a summary of these properties.

What type of rock is rhyolite classified as?

• Organic

• Igneous

• Metamorphic

• Sedimentary

Why is rhyolite considered a felsic rock?

• It contains high amounts of iron

• It is formed deep within the Earth

• It is dark in color

• It contains over 70% silica

How does the rapid cooling of lava affect the crystal size in rhyolite?

• It causes crystals to dissolve

• It has no effect on crystal size

• It results in small crystals

• It results in large crystals

What is the typical density range of rhyolite?

• 1.0 to 1.5 grams per cubic centimeter

• 4.0 to 4.5 grams per cubic centimeter

• 2.4 to 2.6 grams per cubic centimeter

• 3.0 to 3.5 grams per cubic centimeter

What does the term 'aphanitic' indicate about rhyolite's texture?

• Crystals are small and not visible

• The rock is porous

• Crystals are large and visible

• The rock is layered

What type of volcanic eruptions produce rhyolite?

• Violent eruptions

• Eruptions with no lava

• Gentle eruptions

• Underwater eruptions

What happens to extrusive rocks when they make contact with the atmosphere?

• They melt

• They cool slowly

• They expand

• They cool quickly

Which of the following is NOT a characteristic of rhyolite?

• Felsic

• Aphanitic

• Extrusive

• Coarse-grained