Observe Weathering Effects - 4th Grade Science
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Which option is an observation of weathering, not erosion: sand moved downstream or rock cracking in place?
Which option is an observation of weathering, not erosion: sand moved downstream or rock cracking in place?
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Rock cracking in place. Weathering breaks rock in place; erosion moves material away.
Rock cracking in place. Weathering breaks rock in place; erosion moves material away.
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Which observation is evidence of plant root wedging weathering rock?
Which observation is evidence of plant root wedging weathering rock?
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Roots growing into cracks make the cracks larger and split rock. Plant roots exert pressure as they grow, physically breaking rock apart.
Roots growing into cracks make the cracks larger and split rock. Plant roots exert pressure as they grow, physically breaking rock apart.
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What observation best indicates abrasion weathering by wind or water?
What observation best indicates abrasion weathering by wind or water?
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Rock surfaces become smoother and more rounded over time. Repeated rubbing by particles carried in wind or water wears surfaces smooth.
Rock surfaces become smoother and more rounded over time. Repeated rubbing by particles carried in wind or water wears surfaces smooth.
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Identify the weathering type: iron-rich rock turns reddish after long exposure to air and water.
Identify the weathering type: iron-rich rock turns reddish after long exposure to air and water.
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Chemical weathering (oxidation). Oxidation chemically changes iron minerals to rust compounds.
Chemical weathering (oxidation). Oxidation chemically changes iron minerals to rust compounds.
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What is weathering in Earth science?
What is weathering in Earth science?
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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.
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.
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Identify the weathering type: a sidewalk cracks because a tree root grows underneath it.
Identify the weathering type: a sidewalk cracks because a tree root grows underneath it.
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Physical weathering (root wedging). Roots physically break concrete without changing its composition.
Physical weathering (root wedging). Roots physically break concrete without changing its composition.
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What is the difference between weathering and erosion?
What is the difference between weathering and erosion?
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Weathering breaks rock down; erosion moves the broken pieces. Weathering is the breakdown process; erosion is the transport process.
Weathering breaks rock down; erosion moves the broken pieces. Weathering is the breakdown process; erosion is the transport process.
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Which type of weathering happens when rock is broken without changing what it is made of?
Which type of weathering happens when rock is broken without changing what it is made of?
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Physical (mechanical) weathering. Physical weathering changes size and shape but not chemical composition.
Physical (mechanical) weathering. Physical weathering changes size and shape but not chemical composition.
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Which type of weathering changes the minerals in a rock into new substances?
Which type of weathering changes the minerals in a rock into new substances?
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Chemical weathering. Chemical reactions alter the rock's mineral composition.
Chemical weathering. Chemical reactions alter the rock's mineral composition.
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What observation best shows frost wedging (ice weathering) is happening?
What observation best shows frost wedging (ice weathering) is happening?
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Water freezes in cracks and the cracks get wider over time. Ice expands when water freezes, forcing cracks to widen.
Water freezes in cracks and the cracks get wider over time. Ice expands when water freezes, forcing cracks to widen.
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Identify the weathering type: a stream rolls pebbles and they become smooth and rounded.
Identify the weathering type: a stream rolls pebbles and they become smooth and rounded.
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Physical weathering (abrasion). Water tumbling rocks against each other physically wears them smooth.
Physical weathering (abrasion). Water tumbling rocks against each other physically wears them smooth.
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Which option is the best observation of physical weathering: rock rusting or rock breaking into smaller pieces?
Which option is the best observation of physical weathering: rock rusting or rock breaking into smaller pieces?
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Rock breaking into smaller pieces. Breaking is physical change; rusting is chemical change.
Rock breaking into smaller pieces. Breaking is physical change; rusting is chemical change.
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Which observation best supports that weathering has occurred: a boulder breaks into gravel or gravel is carried away?
Which observation best supports that weathering has occurred: a boulder breaks into gravel or gravel is carried away?
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A boulder breaks into gravel. Breaking shows weathering occurred; carrying away shows erosion.
A boulder breaks into gravel. Breaking shows weathering occurred; carrying away shows erosion.
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Which observation best indicates abrasion by moving water?
Which observation best indicates abrasion by moving water?
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Rocks become smoother and more rounded over time. Constant rubbing removes sharp edges and corners.
Rocks become smoother and more rounded over time. Constant rubbing removes sharp edges and corners.
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Which agent most commonly causes abrasion on a windy beach or desert?
Which agent most commonly causes abrasion on a windy beach or desert?
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Wind-blown sand. Sand particles act as natural sandblasters in dry areas.
Wind-blown sand. Sand particles act as natural sandblasters in dry areas.
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What is plant root wedging?
What is plant root wedging?
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Roots growing into cracks and forcing rock apart. Growing roots exert pressure as they expand.
Roots growing into cracks and forcing rock apart. Growing roots exert pressure as they expand.
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What observation best indicates root wedging near a sidewalk or cliff?
What observation best indicates root wedging near a sidewalk or cliff?
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Cracks widened where roots are growing through them. Roots act like wedges, pushing rock apart as they grow.
Cracks widened where roots are growing through them. Roots act like wedges, pushing rock apart as they grow.
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Which chemical weathering process forms rust when iron in rock reacts with oxygen?
Which chemical weathering process forms rust when iron in rock reacts with oxygen?
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Oxidation. Iron combines with oxygen to form iron oxide (rust).
Oxidation. Iron combines with oxygen to form iron oxide (rust).
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What observation best indicates oxidation on rocks or soil?
What observation best indicates oxidation on rocks or soil?
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Reddish-brown staining or a rust-colored coating. Iron minerals oxidize, creating distinctive rust color.
Reddish-brown staining or a rust-colored coating. Iron minerals oxidize, creating distinctive rust color.
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Which weak acid in rainwater can dissolve some rocks such as limestone?
Which weak acid in rainwater can dissolve some rocks such as limestone?
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Carbonic acid. Forms when carbon dioxide dissolves in rainwater.
Carbonic acid. Forms when carbon dioxide dissolves in rainwater.
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