How things work college course/Hunting the Elements (PBS NOVA)
Will do this after the quizzes for Fall 2015 have been completed.
Gold
edit- {Au is the symbol for}
- {All the gold ever mined would fit into a single cube of about}
- {Gold is quite common in the Earth’s crust, but is difficult to mine because it is locked up in granite.}
- {Although modern assaying methods yield more precise estimates, it is usually possible to estimate the quality of ore by counting the density of yellow specks in dirt from ore. }
- {It is unusual to see the gold in gold ore with the naked eye}
- {To assay gold ore is to }determine the quality of gold ore. purify it after it has been mined
- {In ‘Hunting the Elements’, the gold ore from the Cortex mine is first crushed to the consistency of …Gravel sand baby power
- {The fire assay process is ----- years old} 500
- {What fraction by weight of typical gold ore contains actual gold} answer: 32,000 or equivalently 25 pounds per 400 tons
- {About ____ % of the elements are metals} 75%
- { How an atom reacts chemically depends on how willing it is to share electrons with others } true
- { So do other so-called "noble" metals: silver, platinum, palladium,
- { Using cyanide to react with the gold allows them }
- { with a white powder called flux, chemicals that prevent the molten gold from reacting with or sticking to anything }
Copper
edit- { The ancients first learned how to heat rocks to extract copper, at least 7,000 years ago.}
- future's market
- Cu is coper
- malleable
- scares away bacteria
- Tin is Sn
- Tin plus copper is bronze
- {When ‘Hunting the Elements’ visited the Verdin Company, they began the process with a bell, not of ______, but of ______. This bell was used to make a mould of }
- { first manmade metal .alloy was bronze }
- {Which was first used, copper or bronze? }
- {Copper is soft and easy to dent because ..The rows of atoms can easily slide past each other }
- {What makes a metal conduct electricity?}
- define ingot
- An alloy of copper is made hard by the fact that the added atoms are …larger
- In ‘Hunting the Elements’ it is speculated that the libergy bell cracked because of too many atoms other than coppermpurites
- When the molten bronze is poured, what is done to prevent flaws from developing? (pour fast)
- 20-30% of molds fail
electron microscope
edit- Boundaries between grains are actually defects in the orderly arrangement of the atoms. --Crystallite.jpg
- In ‘Hunting the Elements’, Why would an electron microscope be covered on blankets
- In ‘Hunting the Elements’, what could the electron microscope see? Atoms could be seen but not distinguished. (true, distractros include Innelectronsr and outer shell
Atoms and the periodic table
edit- Scale the atom to the size of the nucleous: 10,000 to one
- Scale the atom to the size of the nucleous: 2 miles (3 km) to 3 cm