AIDE Earth Science Key Points Chapter 7 "Minerals"
Lesson 1 "Minerals" Key Vocabulary Terms mineral - element or compound found in the earth. Key Concepts A mineral is a solid, formed naturally in the earth, having the same chemical makeup throughout, not made of living things, and having a definite atomic pattern. Some common minerals are gold, quartz, diamond, carbon, feldspar, mica, calcite, dolomite, halite, or gypsum. Geologists are able to find minerals because they look for clues on the earth's surface. these might include the kinds of rocks or plants in an area. Sometimes geologists test running water for traces of minerals. Minerals are taken out of the earth by being stripped off the earth's surface or dug out of open pits. People reach minerals far underground by digging long shafts. Minerals are purified either by melting them or by using chemicals to break them apart. Did you learn these Objectives? Are you able to explain what a mineral is? Can you name some common minerals. Can you explain how minerals are located and mined?
Lesson 2 "Properties Used to Identify Minerals" Key Vocabulary Terms luster - how a mineral reflects light. streak - color of the mark a mineral makes on a white tile. hardness - ability of a mineral to resist being scratched. Key Concepts Different colors of the same mineral appear because tiny amounts of different minerals, called impurities, can give samples of the same mineral different colors. silver has a white or gray color and a metallic luster. You determine a mineral's streak by rubbing a soft mineral across a white porcelain tile. The color of the mark it leaves is the mineral's streak. A mineral with a higher number is harder than a mineral with a lower number a softer mineral, like quartz, will not scratch a harder mineral like topaz. A mineral that is between 5 and 6 an Moh's hardness scale would be scratched by steel but does not scratch glass. Did you learn these Objectives? Can you identify four properties of minerals? Can you assess color as a wy to identify minerals? Are you able to define luster? Can you describe a streak test? Are you able to explain how to test the hardness of a mineral?
Investigation 7-1 "Observing Color, Streak, and hardness." (Optional, must complete 16 total investigations) Key Concepts In this investigation, you will describe the color streak, and hardness of known mineral samples.
Lesson 3 "Other Physical Properties of Minerals" Key Vocabulary Terms crystal - basic shape that a mineral tends to take. cleavage - ability to split along a flat surface Fracture - tendency to break with jagged edges. specific gravity - mineral's weight compared to the weight of water. Key Concepts The arrangement of atoms determine a crystal's shape. Cleavage is a mineral's tendency to break along flat surfaces, a mineral that fractures leaves a jagged edge. Specific gravity measures the density or a mineral's weight compared to weight of the same volume of water. A mine aral 10 times heavier than water would have a specific gravity of 10. The specific gravity of water is 1. Did you learn these Objectives? Are you able to explain what a crystal is? Can you recognize how minerals break? Can you measure the specific gravity of mineral samples?
Investigation 7-2"Finding Specific Gravity" (Optional, must complete 16 total investigations) Key Concepts In this investigation, you will find the specific gravity of unknown mineral samples.
Lesson 4 "Common Uses of Minerals" Key Concepts A diamond is used to make drill tips because it is the hardest known mineral. Gold and copper are useful in computer parts because they conduct electricity. Glass is made from the mineral quartz. Two types of minerals that make gems are diamond, ruby. There are many minerals we use everyday and they may include: graphite (pencil lead), iron (cars), quartz (glass), bauxite (soft-drink cans) gypsum (wallboard) Did you learn these Objectives? Can you realate the usefulness of minerals to their properties? Are you able to identify minerals that are precious metals or gems?
Chapter Summary and Review See page 174-175 Chapter 7 Review answers are 1.fracture 2.crystal 3.hardness 4.cleavage 5.mineral 6.streak 7.luster 8.specific gravity 9.C 10.B 11.D 12.B 13.A 14.D 15.cinnabar 16.galena 17.Minerals can be skimmed from the earth's surface in a strip mine or dug deep out of the ground by means of long shafts. 18.Weith the sample in the air; then weigh it submerged in water. subtract it weight in water from its weight in air. Divide the weight in air by the difference you calculated in the previous step. this number is the sample's specific gravity. 19.the samples are probably different varieties of the same mineral. 20.By testing the hardness and specific gravity of each mineral, you could determine which was quartz.
