My Notes: Earth Materials Flashcards
Why does CO2 affect temperature?
Because heat gets trapped
What is the greenhouse effect?
Sunlight is reflected (infrared), radiated heat from the ground, trapped by greenhouse gases.
What does the infrared heat up?
Atoms in the atmosphere
What are the 3 greenhouse gases?
H2O (vapour)
CO2 (carbon dioxide)
CH4 (methane)
What happens as CO2 in the atmosphere increases?
More heat in the atmosphere
Last___years, ever___years alternates between hot spell and glaciation.
- 700 000
- 100 000
Why do we have season?
We have seasons because the EArth’s axis is not perpendicular to the plane of its orbit. .Over time, the tilt angle varies with a frequency of 41 000 years
An individual mineral has a___chemical composition.
fixed
Where does olivine come from?
meteorites
What is olivine (gem quality) called?
peridot
How many different chemical compositions of minerals are there?
2000 or 6000 depending on whether you count the variants.
What is the shape of minerals controlled by?
arrangement of internal atoms
Doe crystals depend on size?
no only shape
How many fundamentally different crystal forms are there? How many variant does each for have?
- 7 forms
- about 6 variants each
Is sodium smaller or larger than chlorine?
smaller
True of false: each crystal has its own crystal lattice structure.
true
What is the difference between cleavage and fracture?
Cleavage: controlled by the unit cell geometry
Fracture: break not controlled by the unit cell geometry
True or false: many minerals will produce repetitive cleavage shape when you break them.
true
What can colour derive from?
- colour can derive from the way the objet handles light in some cases
- chemical composition
- trace elements
- way atoms are put together
What are trace elements?
Don’t take part in crystal elements–get accidentally trapped.
What causes hardness with the element carbon?
Diamonds (hard): form under high pressure and temperature, carbons atoms arranged so that every carbon atoms is as far away as it is close from its closest one, dense 3D package
Graphite: forms under lower pressure and temperature, atoms well bound and close together in a series of hexagons forming sheets of hexagons, sheets attached to other sheets by weak electrostatic force so they break easily
What controls harness for all minerals?
Way crystal lattice is.
How do minerals grow?
Minerals grow by adding atoms to what is already there
