A student wants to model the physical weathering of rock. Which activity could the student perform?
A. Place drops of acid on chalk, and then observe the chemical reaction.
B. Place ice cream in a bowl, and then watch it melt.
C. Place several cookies in a box, and then shake the box.
D. Place a paper boat in a ditch, and then use water from a hose to make it sail away.
Physical weathering, also known as mechanical weathering, is the process of breaking down rocks through physical processes like temperature changes, freezing and thawing, abrasion, and mechanical stress without changing the rock's chemical composition.
Option A (Place drops of acid on chalk, and then observe the chemical reaction) describes a chemical weathering process because the acid would chemically react with the chalk, which is made of calcium carbonate, resulting in chemical changes.
Option B (Place ice cream in a bowl, and then watch it melt) represents a phase change (from solid to liquid) but does not model the physical weathering of rock.
Option D (Place a paper boat in a ditch, and then use water from a hose to make it sail away) illustrates the movement of an object by water but does not demonstrate the physical weathering process.
Option C (Place several cookies in a box, and then shake the box) is the most appropriate choice to model physical weathering. By shaking the box with cookies inside, you would mimic the physical processes like abrasion and grinding that happen to rocks in nature. The contact between the cookies inside the shaking box would break pieces off the cookies, symbolizing the way rocks break apart during physical weathering.