___∆ 1. Erosion is / is not caused by water, ice, wind, chemicals, and sand. (pick one)
__ ∆ 2. The process of ____________ causes rocks on the Earth’s surface to change, crumbling mountains
and widening valleys.
__ ∆ 3. When solids / liquids are carried away by water, it is also considered a form of erosion. ( pick one)
__ ∆ 4. When liquid water _______________ in rock it expands and causes rocks to erode by cracking them.
__ ∆ 5. When rain combines with ______________ in rock, it forms rust, which is a form of chemical erosion.
__ ∆ 6. When softer rock erodes faster than the harder rock above, sometimes a(n) ___________ is formed.
__ ∆ 7. Wind sometimes picks up sand / boulders and blows them into rocks causing the rock to erode. ( pick one)
__ ∆ 8. Erosion is the slow wearing away of the earth’s __________________ over millions of years.
__ ∆ 9. When __________________ are hit by waves over thousands of years, a beach of sand is formed.
__ ∆ 10. Sand, ________________ and waves hit rocks and smooth out the surface of older rocks.
__ ∆ 11. ___________ can hold back soil from eroding and also break rocks apart – causing erosion.
__ ∆ 12. Water flows into cracks of rocks and shrinks / expands when it freezes causing the rock to crack. (pick one)
__ ∆ 13. As water flows over rocks, it dissolves minerals causing different ___________ to sometimes appear.
__ ∆ 14. Pounding water, wind, __________________ and rain are major causes of erosion.
__ ∆ 15. Chemicals in the air / plants contribute to erosion. (pick one)