Exam 1 Part 3 Flashcards
Study for first exam
How many elements are in the world and how many are naturally occuring?
There are 100 known elements and 92 are naturally occuring.
What are the 8 elements that we need to know?
1) Fe (Iron
2) Mg (Magnesium)
3) Na (Sodium)
4) Ca (Calcium)
5) K (Potassium)
6) Al (Aluminum)
7) Si (Silicon)
8) O (Oxygen)
What is an Atom?
Smallest particle of matter
What are elements made of?
Atoms. A single type of atom
How do you calculate atomic weight?
The protons + neutrons + electrons
How can you change the weight of an element but keep it the same?
By changing the number of neutrons
What changes an element?
The number of protons
How do you calculate the atomic number of an element?
By counting how many protons it has
What is a covalent bond?
A covalent bond is when two element atoms are sharing electrons to become stable.
What is an ionic bond?
An ionic bond is when one element atom, steals from another in order to make itself stable and also makes the element that it stole from stable
What is metallic bonding?
When electrons are free to mingle among atoms.
What is the strongest bonding and what is the weakest?
Covelent bonding (diamonds) is the strongest while metallic is the weakest.
How do you calculate mass number in an element?
Neutrons + protons
What is an isotope?
Different number of neutrons but same number of protons, making it the same element but with different atomic mass number
What do unstable isotopes do?
They emit particles known as radioactive decay
What do minerals consist of?
They consist of an orderly array of atoms that are chemically bonded to create a crystalline structure
What are polymorphs?
They are minerals with the same composition but different crystaline structures
Example of two minerals that are polymorph?
Diamonds and graphite, if they are slow to the surface they are graphite. Diamonds are in the ground before turning into graphite.
What are the seven ways to describe the physical properties of a mineral?
1) Luster
2) Crystal form
3) Color
4) Streak
5) Hardness
6) Cleavage
7) Fracture
How do you know what the streak is of a mineral?
The streak is the powdered form of a mineral, you obtained it by scraping it on an unglazed porcelain plate
What is the hardness of a mineral?
How hard it is to scratch it on the moh’s 1-10 scale
What is a cleavage?
When a mineral is broken and it breaks into planes
What is a fracture?
When a mineral is broken and it doesn’t have a cleavage at all
How do you calculate the specific gravity of a mineral?
By dividing it’s weight by an equal volume of water.
What are two examples of heavy minerals?
Lead or gold
What is the crust composed of mineral wise?
It’s 50 percent feldspar and 8 percent non-silicates
What is the most common mineral?
Feldspars
What is silicate?
The most important mineral group comprised most rock forming mineral
What is the feldspar group and what are their cleavages?
They are light silicates, two perfect cleavages that make 90 degrees
What is the name of a potassium feldspar and what is the same of the sodium feldspar?
Orthoclase and Plagioclase
What happens when you add water to feldspar?
It will form clay
What happens when you add water to quartz?
Not much. Nothing at all.
How much of the earth’s crust is clay?
5%
What is quartz?
It’s light colored silicate, only common silicate that is composed entirely of oxygen and silicon
What are the three most common components of magma?
1) Liquid portion (Melt)
2) Solids (Sometimes has silicates)
3) Volatiles (Dissolved gases in the melt)
What is texture and why is it important?
Texture is the size and arrangement of mineral grains, it’s important because it can tell where magma cooled.
How would the crystal size be affected by how fast or how slow they cooled?
If they cooled slowly then there would be fewer but larger crystals, if fast there would be more but smaller crystals and if very fast there would be no crystals just glass.
What can granite’s crystals tell you about it?
It can tell you about how fast it cooled and therefor tell you about where it was formed.
If granite is formed intrusively, why is it we can find it on or near the surface?
Erosion.
What are the four igneous crystal textures?
1) Aphanitic (Micro crystals, can’t be seen)
2) Phaneritic (Large crystals)
3) Vesicular (Bubble texture)
4) Prophyritic (Larger crystals in a matrix of smaller crystals)
What are dark silicates?
Ferromagnesian
What are light silicates?
Non-ferromagnesian
What are the 3 light silicates
Quartz, mica, and clay minerals
What are 3 dark silicates?
Olivine group, proxene group, and amphibole group
What is the specific gravity of a mineral?
It’s the density of the mineral, how heavy it is
