The Rock Cycle

Question 1

Sam is describing a rock’s journey. Which sentence from Sam’s description shows that the rock cycle never has a first rock and keeps going forever?

Accepted Answer

After the slate melts, the new magma can become lava again, so the cycle continues without a starting point.

Answer

When the rock turns into soil, the cycle ends because soil cannot become a rock again.

Answer

The rock changes from sand to sandstone and then stops because sandstone is the final form.

Answer

The rock begins as lava that cools into igneous stone, then the story starts.

Question 2

Lena learns that a piece of igneous rock can become sedimentary, then metamorphic, and finally melt back into magma. Which statement best explains why this entire journey cannot be completed in just a few years like a human lifetime?

Accepted Answer

The rock must first be broken down into tiny pieces by wind and water, those pieces must be squeezed together for many thousands of years, then deep underground they must be heated and pressed before they melt, and each of those steps takes a very long time.

Answer

Wind can turn the rock into a new type of rock in a few days, and the heat from a campfire melts it right away.

Answer

A single earthquake’s pressure is enough to turn the rock into metamorphic rock, which then instantly melts.

Answer

The rock can melt as soon as it is hit by sunlight, so the whole cycle finishes quickly.

Question 3

Which of the following sequences correctly shows a rock changing from igneous to sedimentary to metamorphic and then back to igneous?

Accepted Answer

Igneous → weathering → sediment → sedimentary → heat and pressure → metamorphic → melting → igneous

Answer

Igneous → melting → igneous → weathering → sediment → sedimentary → heat and pressure → metamorphic

Answer

Igneous → sediment → sedimentary → weathering → metamorphic → heat and pressure → melting → igneous

Answer

Igneous → heat and pressure → metamorphic → weathering → sediment → sedimentary → melting → igneous

Try three questions

Sam is describing a rock’s journey. Which sentence from Sam’s description shows that the rock cycle never has a first rock and keeps going forever?

Lena learns that a piece of igneous rock can become sedimentary, then metamorphic, and finally melt back into magma. Which statement best explains why this entire journey cannot be completed in just a few years like a human lifetime?

Which of the following sequences correctly shows a rock changing from igneous to sedimentary to metamorphic and then back to igneous?

Keep going on this shelf