8th Grade Science Test 3

Question 1

the largest group of minerals, which compose over 90% of the earth’s crust

Answer 1

silicates

Question 2

the layer of solid rock below the soil

Answer 2

bedrock

Question 3

the rarest, most durable, and most beautiful minerals

Answer 3

precious stones

Question 4

substances that are found naturally in the earth and have a crystalline structure

Answer 4

minerals

Question 5

a theory that has never been proven false

Answer 5

law

Question 6

chemical sediments that result from the evaporation of water

Answer 6

evaporites

Question 7

a well-known chemical sedimentary rock

Answer 7

limestone

Question 8

a soil substance composed of decayed organisms’ particles

Answer 8

humus

Question 9

the most famous measure of earthquake strength, which rates earthquakes on a scale of 1 to 10

Answer 9

Richer magnitude scale

Question 10

rocks that have a smooth,glasslike texture

Answer 10

amorphous

Question 11

earthquake zone that includes the San Andreas Fault

Answer 11

circum-Pacific belt

Question 12

the metal that is more valuable than gold or silver

Answer 12

platinum

Question 13

hard, round structures that form when minerals settle out of water and crystallize around a sand grain or other mineral fragment

Answer 13

concretions

Question 14

the measure of the pull of gravity on an object

Answer 14

weight

Question 15

the group on which a test is performed

Answer 15

experimental group

Question 16

a volcano that will probably not erupt again

Answer 16

extinct

Question 17

beryl that has a deep green color

Answer 17

emerald

Question 18

the third step in the scientific method

Answer 18

formulate a hypothesis

Question 19

the inner core of the earth is thought to be

Answer 19

solid

Question 20

a metal mixture of iron and carbon

Answer 20

steel

Question 21

brass is an alloy of

Answer 21

copper and zinc

Question 22

mining that uses a rotating drum that travels down a long track while grinding coal

Answer 22

longwall mining

Question 23

crystals are generally characterized by many flat surfaces called

Answer 23

faces

Question 24

the most basic unit of matter

Answer 24

atoma

Question 25

about 80% of the world's earthquakes occur in

Answer 25

the circum-Pacific belt

Question 26

the breakdown of organisms is known

Answer 26

decomposition

Question 27

any piece of solid volcanic ejecta

Answer 27

pyroclast

Question 28

type of rock formed when magma solidifies

Answer 28

igneous rock

Question 29

type of rock formed when deposits of sand and mineral fragments are cemented together

Answer 29

sedimentary rock

Question 30

type of rock formed when preexisting rocks are altered by heat or pressure

Answer 30

metamorphic rock

Question 31

any mineral that contains a valuable metallic element

Answer 31

ore

Question 32

the branch of geology that deals with the identification and classification of minerals

Answer 32

mineralogy

Question 33

the bending or buckling of rocks under great force produces

Answer 33

a fold

Question 34

aluminum is refined from the common mineral

Answer 34

bauxite

Question 35

the most abundant metal in the earth's crust

Answer 35

aluminum

Question 36

the type of soil that contains a mixture of sand, silt, clay, and humus

Answer 36

loam

Question 37

the change of one type of rock into a new type of rock

Answer 37

metamorphism

Question 38

the number that compares an object's density to the density of water

Answer 38

specific gravity

Question 39

the study of soil

Answer 39

pedology

Question 40

the hardest naturally occurring known substance

Answer 40

diamond

Question 41

a mineral that remains glowing after being exposed to ultraviolet light and then placed in the dark exhibits

Answer 41

phosphorescence

Question 42

the most common element in the earth's crust

Answer 42

oxygen

Question 43

a "self pumping" well

Answer 43

artesian well

Question 44

a substance with a pH of 10

Answer 44

basic

Question 45

the most common of all igneous rocks

Answer 45

basalt

Question 46

igneous rock with a smooth, glasslike texture; known as "volcanic glass"

Answer 46

obsidian

Question 47

the most common sedimentary rock

Answer 47

shale

Question 48

rock that consists of smooth pebbles embedded in hardened sand or clay

Answer 48

conglomerate rock

Question 49

an organic sedimentary rock that is also called a fossil fuel

Answer 49

coal

Question 50

term that refers to the way light is reflected from the surface of a mineral crystal

Answer 50

luster

Question 51

What do mineralogists call an element that occurs naturally in its pure form, uncombined with other elements?

Answer 51

native element

Question 52

What is a single layer of sedimentary rock called?

Answer 52

stratum

Question 53

What nutrient makes a plant's fruits "firm up" properly?

Answer 53

phosphorus

Question 54

What is another name for a bar of refined gold?

Answer 54

bullion

Question 55

What is an alloy of iron, carbon, and nickel or chromium?

Answer 55

stainless steel

Question 56

What are geometric structures composed of atoms or molecules in an orderly arrangement?

Answer 56

crystals

Question 57

name the arrow zone of active volcanoes that nearly encircles the Pacific basin.

Answer 57

Ring of Fire

Question 58

What type of lava has a smooth texture with a "ropy" appearance?

Answer 58

pahoehoe

Question 59

What mineral test leaves a line of powder on a plate?

Answer 59

streak test

Question 60

What are the upper layers of the ground stripped away by surface mining called?

Answer 60

overburden

Question 61

What is the name for a substance that is composed of only one type of atom?

Answer 61

element

Question 62

earthquake wave that vibrate at right angles to the direction of wave travel

Answer 62

S waves

Question 63

point at which an earthquake begins

Answer 63

focus

Question 64

weak earthquake

Answer 64

tremor

Question 65

fastest earthquake waves

Answer 65

P waves

Question 66

term for small earthquakes that follow an earthquake for days or even months

Answer 66

aftershock

Question 67

rocks on either side of a fault spring back to a position of little or no strain

Answer 67

elastic rebound

Question 68

giant sea waves

Answer 68

tsunamis

Question 69

instrument that records and studies the vibrations from an earthquake

Answer 69

seismograph

Question 70

point on earth's surface directly above where an earthquake began

Answer 70

epicenter