Chapter 6, Lesson 1
Element: pure substance; cannot be broken down
Mineral: solid, natural material made from non-living substances in the ground
Some are single element ; others are combinations
Properties of Minerals
Color: refers to the surface color
Streak: color left when rubbing mineral onto a surface
Luster: way mineral reflects light (metallic, non-metallic)
Cleavage: number of planes along which a mineral breaks
Fracture: property of uneven/rough surfaces
Shapes of Minerals
Crystals: solid whose shape forms a fixed pattern (geometric shapes)
Gems: mineral that is rare, beautiful, transparent, and shines in light
Ore: minerals mixed with other substances
Rock Cycle: change from one type of rock to another
Rock: solid object made naturally in Earth’s crust
Sedimentary Rock: forms from sediments
Igneous Rock: forms as lava cools/hardens
Intrusive: igneous rock formed inside earth; has large crystals
Extrusive: lava that cools on the surface; small crystals
*obsidian-no crystals
Metamorphic Rock: forms when sedimentary and igneous change under heat and pressure
Shape and size of crystals can change under this pressure; layers can form
Chapter 6, Lesson 2
Organic: having to do with or coming from living things
Soil: mixture of rock and once living parts of plants and animals; formation starts with weathering of
rocks
Soil Horizon: layer of soil
A Horizon – topsoil; most plants grow here
Humus: made of decayed organic material; feeds plants, soaks up and holds water
B Horizon – subsoil
Less humus; fine rocks; clay
C Horizon – larger pieces of weathered rock resting on bedrock
Forest Soil: thin layer of topsoil; little humus
Desert Soil: not much humus
Grassland & Prairie Soil: rich in humus; good for farming
Pollution: harmful materials added to soil, air, and water
Conservation: the protection of natural resources, including soil
Fertilization: replace lost nutrients
Crop Rotation: change crops yearly
Strip Farming: grass between crops
Contour Plowing: curves on hills
Terracing: levels on hills
Wind Breaks: trees on edge
Chapter 6, Lesson 3
Fossils: the remains of ancient organisms preserved in soil or rock; found in sedimentary rock
Fossil Fuels: formed from the decay of ancient organisms and used today for energy
Bituminous coal: soft coal
Anthracite: hard coal
Oil and natural gas are formed from decayed ocean organisms under heat, weight, and bacteria
Law of Superposition: each layer of rock is younger than the one below it
Fossil age determined by age of rock
Relative Age: age compared to another rock
Absolute Age: age in years
Alternative Energy Source: any source other than fossil fuel
Wind: windmills generate electricity
Water: hydroelectricity
Solar: from the sun; inexhaustible
Geothermal: from deep inside earth
Nuclear: changes in atoms
Chapter 6, Lesson 4
97% of water is salt water
Saltwater is made when rain runs downhill and picks up salts from soil and rock
Running Water: streams and rivers
Standing water: lakes and reservoirs
Groundwater: beneath the surface
Aquifer: underground layer of rock or soil that absorbs water
Water Treatment
Coagulation: attract dirt
Sedimentation: dirt falls to bottom
Filtration: remove remaining bits
Disinfection: chlorine added
Smog: yellow haze produced when fossil fuels are burned
Ozone: a form of oxygen that protects living things from radiation