Unit 5 Minerals Study Guide KEY Overview - The rock cycle, which is continual in nature, explains the formation of minerals and rocks. Fossils provide evidence of constant environmental change. Standards: Students will investigate the scientific view of how the earth’s surface is formed. Investigate the contribution of minerals to rock composition. Describe how fossils show evidence of the changing surface and climate of the Earth. Students will investigate the scientific view of how the earth’s surface is formed. Compare and contrast the Earth’s crust, mantle, and core including temperature, density, and composition. Questions: - Students will be asked to answer these questions throughout this unit of study. #1 How are minerals identified? #2 How do natural objects compare to manufactured objects? #3 How are minerals used by 6th graders? MINERALS 1. Minerals which are naturally existing chemical compounds. 2. Minerals can be identified by their physical properties. 3. What are the four characteristics of a mineral? Naturally occurring, Crystal Structure/Chemical Substance, Inorganic/ Non-Living, and Solid. 4. Minerals are classified based on chemical composition into two groups. What are these two groups? silicates and nonsilicates. 5. The two most common elements in the Earth's crust are oxygen & silicon and that is why geologists label all minerals as either silicates or nonsilicates. 6. Minerals that contain combinations of silicon and oxygen in their chemical structure are called silicates and minerals without silicon and oxygen are called nonsilicates. 7. The structure of a crystal is made by a repeating pattern of atoms. The largest crystals are formed as superheated rocks slowly cool. Where are these large crystals formed? Underground near magma. IDENTIFYING MINERALS 8. The following physical properties of minerals can be easily used to identify a mineral: 1. 2. 3. 4. 5. 6. 7. 8. 9. Color Streak Hardness Cleavage or Fracture Crystalline Structure Magnetism Luster Chemical Composition Specific Gravity (density) 9. What is Mohs' hardness scale? A scale from 1 to 10 that measures the hardness of rocks. 10. Minerals are identified by Hardness is tested by scratching 11. What physical properties can be expressed in numbers and shows how that substance withstands being scratched? Hardness 12. On Mohs' hardness scale, talc is the softest mineral and diamond is the hardest. 13. What is a mineral's streak? The powder left behind when a mineral scratches against a streak plate. 14. The color of the powder that a mineral leaves on a piece of white, unglazed porcelain is called Streak. 15. Cleavage is the tendency of minerals to break along flat surfaces and fracture is the tendency to break in an uneven manner. 16. Quartz breaks unevenly and this is called fracture. 17. A diamond breaks evenly and this is called cleavage. 18. Of the mineral properties, color is the least accurate for figuring out a mineral’s identity. 19. The most common classification of minerals is based on chemical composition. 20. Luster is how light reflects off the mineral. 21. Metallic and nonmetallic describes a mineral's luster. 22. This is considered a special property that applies to only a few minerals? Magnetism. 23. The purest color of quartz is clear because it has the fewest impurities inside of it. Rocks vs. Minerals 24. Rocks and minerals are naturally occurring substances that are usually crystalline and solid 25. Igneous rocks are dominated by silicate minerals. 26. Rocks and minerals are not the same thing. 27. Rocks are composed of minerals which are naturally existing chemical compounds. 28. Minerals are the building blocks of rocks. 29. Rocks are composed (made up) of minerals. 30. FALSE (True OR False) A mineral can have more than one type of rock in it. 31. TRUE (True OR False) A rock can have more than one type of mineral in it. Minerals in everyday life 32. Almost every product we use in daily life contains depends on minerals that have to be mined. 33. Many materials used by people come from rocks and minerals. 34. We use carbonate minerals in cement, building stones, and fireworks. 35. Carbonates are minerals that contain both carbon and oxygen. 36. Silicon is the second most common element on Earth. 37. List some commonly used minerals. Aluminum – packaging, building/construction, electrical, machines Barium – rubber, sparkplugs, white pigment Beryllium – X-rays, computers, electronics in cars, medical equipment Copper – cables, wires, switches, plumbing, heating Feldspar – paper, pottery, glass, fertilizer Halite (salt) – preserving food, seasoning food, soap, mineral water Lead – batteries, gas, electronics, glass construction, computers Lithium – batteries, glass, medicine Silica – computer chips, glass, cosmetics, medicine Titanium – sports equipment, welding, missiles, jet engines, medical Uranium – submarines, nuclear medicine VOCABULARY mineral formation, pressure, organic, inorganic, structure, fracture, luster, cleavage, carbonate, silicate, streak