Lecture 3- Minerals And Rocks

Question 1

What are the three classifications of rocks

Answer 1

Igneous, Sedimentary and Metamorphic

Question 2

What are igneous rocks? What are a few of their properties?

Answer 2

Rocks formed when molten material/magma or lava cools and solidifies. They appear to have crystals and are NEVER layered.

Question 3

What are the two types of igneous rocks?

Answer 3

Intrusive and extrusive igneous rocks

Question 4

What are sedimentary rocks?

Answer 4

Rocks formed from sediments, bits of preexisting rocks and pieces of once-living organisms (ex: mollusks and other invertebrates

Question 5

What are 3 properties of sedimentary rocks

Answer 5

-Have layers
-Feel gritty (fought texture/feels like it is coated in sand
-Often break easily

Question 6

give 3 examples of sedimentary rocks

Answer 6

• chalk
• coal
• sandstone
  (see ppt slide 3 for more)

Question 7

What are metamorphic rocks?

Answer 7

Igneous or sedimentary rocks that have been transformed by high pressure, high heat, and/or contact with hot magma

Question 8

Where are metamorphic rocks found?

Answer 8

-Deep in the earth
-Where tectonic plates meet

Question 9

give 3 examples of metamorphic rocks

Answer 9

• marble
• slate
• soapstone

Question 10

True or False: Metamorphism melts rocks

Answer 10

FALSE. It just turns them into denser rocks (more compact)

Question 11

Where does molten rock/magma (that will later form igneous rocks) originate within the earth?

Answer 11

-Tectonic Plate Boundaries
-Hot spots

Question 12

How are intrusive igneous rocks formed

Answer 12

Magma trapped below the surface cools slowly, solidifying over thousands or millions of years

Question 13

What is another way of naming intrusive igneous rocks?

Answer 13

Plutonic igneous Rocks since Pluto= Ancient Roman god of the underworld

Question 14

Why does mineral crystal in intrusive igneous rocks have time to grow to larger sizes?

Answer 14

It cools slowly

Question 15

What is the texture of intrusive igneous rocks

Answer 15

Coarse Grained Texture (crystals are visible)

Question 16

give 4 examples of intrusive igneous rock

Answer 16

• diorite
• granite
• gabbro
• pegmatite

Question 17

Why do the first crystals have more regular shapes?

Answer 17

Because they can grow more freely into surrounding molten rocks

Question 18

Why do later forming crystals have weirder shapes?

Answer 18

Because they are forced to fill irregular spaces remaining between previously solidified/neighbouring minerals.

Question 19

What happens with extrusive rocks?

Answer 19

They form when Magma/lava exits a volcano or rises up to surface through a fissure.

Question 20

give 4 examples of extrusive igneous rocks

Answer 20

• basalt
• andesite
• scoria
• rhyolite

Question 21

What is a fissure

Answer 21

À crack/fracture in the rock

Question 22

Where does magma cool when it exits the volcano

Answer 22

Right above or very near to the earth’s surface

Question 23

Why does the magma/lava begin to cool/solidify instantaneously when it leaves the volcano?

Answer 23

Because of the cooler temperatures at the surface (than when they were underground) They are shocked

Question 24

What is an extrusive rock with a glassy texture

Answer 24

Obsidian

Question 25

What is the texture of extrusive igneous rocks

Answer 25

Fine grain texture (crystals are too small to see with naked eye)

Question 26

What does it mean when extrusive igneous rocks have a glassy texture

Answer 26

They do not contain mineral crystals

Question 27

What is an example of a rock with gas bubbles trapped within

Answer 27

Scoria

Question 28

Pyroplastics/scoria rocks are released by what kind of volcanoes?

Answer 28

???

Question 29

What is a rock?

Answer 29

A naturally occurring solid mass/object made of one or more geological materials

Question 30

Geological materials inclue what? (4)

Answer 30

- Mineral crystals - non mineral solids - bits of other rocks - fossils

Question 31

What is the difference between organic and inorganic geological materials?

Answer 31

Organic= have carbon and carbon-hydrogen bonds Inorganic= Generally no carbon and definitely NO carbon-hydrogen bonds

Question 32

What is a crystal

Answer 32

Solids whose atoms/molecules/ions are arranged in a “highly ordered” repeating pattern. They have a highly ordered MICROSCOPIC arrangement of atoms

Question 33

True or false: All solids are crystalline solids

Answer 33

False, not all solids are crystalline solids

Question 34

What is a non-crystalline rock called and what does it mean

Answer 34

It is called amorphous, a substance whose atoms are NOT arranged in a “highly ordered pattern”

Question 35

What is an example of a solid igneous rock that is non-crystalline

Answer 35

Obsidian

Question 36

What is the name of solids that have atoms with highly ordered repeating pattern

Answer 36

Crystalline solids

Question 37

What is crystallization

Answer 37

Process by which crystals form and grow

Question 38

True or False: Macroscopically, crystals have specific geometric shapes with flat surfaces

Answer 38

True

Question 39

What are three crystals

Answer 39

SiO2 (quartz) NaCl (Halite) and H2O (water)

Question 40

What is a mineral (6 things)

Answer 40

1) Inorganic 2) Naturally occurring 3) Homogenous solid 4) with definite chemical composition 5) and ordered/crystalline atomic structure

Question 41

What does inorganic mean?

Answer 41

-Not made up of living matter -Not derived/originating from living matter Not made up of organic materials (organic materials= carbon or carbon-hydrogen bonds)

Question 42

What are two conditions for something to be naturally occurring:

Answer 42

-must be formed/occur naturally -cannot be human-made or manufactured from a lab

Question 43

What is MICA (4 things)

Answer 43

-a silicate mineral -individual mica crystals can be split into thin elastic sheets -MICA common in igneous and metamorphic rocks -Silicates are combination of silicon and oxygen

Question 44

what is silicate

Answer 44

combination of silicon and oxygen

Question 45

What is a homogenous solid? (5)

Answer 45

-Solid -Chemically uniform (same substance throughout) -physically uniform (same appearance throughout) -same crystals/organication of atoms/molecules/ions throughout -Observe same things microscopically and macroscopically throughout the sample

Question 46

TALC: (4 things)

Answer 46

-A silicate mineral -TALC is the “softest” mineral -Used to make baby powder in powdered form

Question 47

What is pyrite (fool’s gold) (4 things)

Answer 47

- FeS2 -Most abundant sulfide mineral -sulfide minerals are minerals containing S2- ion -Pyr = Greek for fire. Pyrite emits sparks when struck with metal