All flashcards
Flashcard 1: Which option is an observation of weathering, not erosion: sand moved downstream or rock cracking in place?
Answer: Rock cracking in place. Weathering breaks rock in place; erosion moves material away.
Flashcard 2: Which observation is evidence of plant root wedging weathering rock?
Answer: Roots growing into cracks make the cracks larger and split rock. Plant roots exert pressure as they grow, physically breaking rock apart.
Flashcard 3: What observation best indicates abrasion weathering by wind or water?
Answer: Rock surfaces become smoother and more rounded over time. Repeated rubbing by particles carried in wind or water wears surfaces smooth.
Flashcard 4: Identify the weathering type: iron-rich rock turns reddish after long exposure to air and water.
Answer: Chemical weathering (oxidation). Oxidation chemically changes iron minerals to rust compounds.
Flashcard 5: What is weathering in Earth science?
Answer: The breaking down of rock into smaller pieces at Earth’s surface. Weathering occurs at the surface where rock is exposed to weather and environmental forces.
Flashcard 6: Identify the weathering type: a sidewalk cracks because a tree root grows underneath it.
Answer: Physical weathering (root wedging). Roots physically break concrete without changing its composition.
Flashcard 7: What is the difference between weathering and erosion?
Answer: Weathering breaks rock down; erosion moves the broken pieces. Weathering is the breakdown process; erosion is the transport process.
Flashcard 8: Which type of weathering happens when rock is broken without changing what it is made of?
Answer: Physical (mechanical) weathering. Physical weathering changes size and shape but not chemical composition.
Flashcard 9: Which type of weathering changes the minerals in a rock into new substances?
Answer: Chemical weathering. Chemical reactions alter the rock's mineral composition.
Flashcard 10: What observation best shows frost wedging (ice weathering) is happening?
Answer: Water freezes in cracks and the cracks get wider over time. Ice expands when water freezes, forcing cracks to widen.
Flashcard 11: Identify the weathering type: a stream rolls pebbles and they become smooth and rounded.
Answer: Physical weathering (abrasion). Water tumbling rocks against each other physically wears them smooth.
Flashcard 12: Which option is the best observation of physical weathering: rock rusting or rock breaking into smaller pieces?
Answer: Rock breaking into smaller pieces. Breaking is physical change; rusting is chemical change.
Flashcard 13: Which observation best supports that weathering has occurred: a boulder breaks into gravel or gravel is carried away?
Answer: A boulder breaks into gravel. Breaking shows weathering occurred; carrying away shows erosion.
Flashcard 14: Which observation best indicates abrasion by moving water?
Answer: Rocks become smoother and more rounded over time. Constant rubbing removes sharp edges and corners.
Flashcard 15: Which agent most commonly causes abrasion on a windy beach or desert?
Answer: Wind-blown sand. Sand particles act as natural sandblasters in dry areas.
Flashcard 16: What is plant root wedging?
Answer: Roots growing into cracks and forcing rock apart. Growing roots exert pressure as they expand.
Flashcard 17: What observation best indicates root wedging near a sidewalk or cliff?
Answer: Cracks widened where roots are growing through them. Roots act like wedges, pushing rock apart as they grow.
Flashcard 18: Which chemical weathering process forms rust when iron in rock reacts with oxygen?
Answer: Oxidation. Iron combines with oxygen to form iron oxide (rust).
Flashcard 19: What observation best indicates oxidation on rocks or soil?
Answer: Reddish-brown staining or a rust-colored coating. Iron minerals oxidize, creating distinctive rust color.
Flashcard 20: Which weak acid in rainwater can dissolve some rocks such as limestone?
Answer: Carbonic acid. Forms when carbon dioxide dissolves in rainwater.
Flashcard 21: What landform observation is strong evidence that limestone has dissolved?
Answer: Caves, sinkholes, or widened cracks in limestone. Carbonic acid dissolves limestone, creating these features.
Flashcard 22: Which statement correctly compares weathering and erosion?
Answer: Weathering breaks rock; erosion moves the broken material. Key difference: weathering is breakdown, erosion is transport.
Flashcard 23: Which term means rock is broken down but not moved to a new place?
Answer: Weathering. Breaking down happens in place, while erosion involves movement.
Flashcard 24: Which type of weathering breaks rock without changing what it is made of?
Answer: Physical (mechanical) weathering. Rock composition stays the same, only size and shape change.
Flashcard 25: Which type of weathering changes rock into new substances?
Answer: Chemical weathering. Reactions with water, oxygen, or acids create different minerals.
Flashcard 26: What observation best shows physical weathering on a rock surface?
Answer: Cracks, chips, or smaller broken pieces of the same rock. Physical weathering only changes size, not composition.
Flashcard 27: What observation best shows chemical weathering on a rock surface?
Answer: Color change, rust-like coating, or a rough, crumbly surface. Chemical reactions alter minerals, changing appearance.
Flashcard 28: Which observation best supports the claim that weathering is changing a hillside?
Answer: Loose rock fragments and soil forming from previously solid rock. Weathering creates loose material from solid bedrock.
Flashcard 29: Which observation best indicates abrasion by moving water?
Answer: Rocks becoming smoother and more rounded over time. Water carries sediment that grinds away sharp edges.
Flashcard 30: What is abrasion in weathering?
Answer: Rock surfaces wearing down by rubbing or scraping. Physical wearing caused by particles grinding against rock.