CHAPTER 01: The Earth in Context

MULTIPLE CHOICE

	1.	Our Sun belongs to a galaxy known as ________.
a.	Andromeda	c.	the Milky Way	
b.	Cepheus	d.	the Stratosphere	

ANS:	C	DIF:	Easy	REF:	1.2	
OBJ:	Understand modern concepts concerning the basic architecture of our Universe and its components.	MSC:	Remembering		

	2.	The ________ theory states that the Universe is continually growing.
a.	Big Bang	c.	nebular expansion	
b.	expanding universe	d.	heliocentric	

ANS:	B	DIF:	Moderate	REF:	1.2	
OBJ:	Understand modern concepts concerning the basic architecture of our Universe and its components.	MSC:	Remembering		

	3.	________ is the study of the history and structure of the Universe.
a.	Geology	c.	Physics	
b.	Geophysics	d.	Cosmology	

ANS:	D	DIF:	Moderate	REF:	1.1	
OBJ:	Understand modern concepts concerning the basic architecture of our Universe and its components.	MSC:	Remembering		

	4.	Compared to our Sun, first-generation stars tend to be ________.
a.	larger in mass and cooler	c.	smaller in mass and cooler	
b.	larger in mass and hotter	d.	smaller in mass and hotter	

ANS:	B	DIF:	Easy	REF:	1.3	
OBJ:	Understand modern concepts concerning the basic architecture of our Universe and its components.	MSC:	Understanding		

	5.	Atoms that are heavier than iron are generally produced by ________.
a.	fission reactions within stars	c.	explosions of supernovas	
b.	fusion reactions within stars	d.	the Big Bang	

ANS:	C	DIF:	Difficult	REF:	1.4	
OBJ:	Understand modern concepts concerning the basic architecture of our Universe and its components.	MSC:	Understanding		

	6.	Using the image below of an atom, where are the protons located?

a.	A	c.	C	
b.	B	d.	D	

ANS:	D	DIF:	Easy	REF:	Box 1.1	
OBJ:	Understand modern concepts concerning the basic architecture of our Universe and its components.	MSC:	Applying

	7.	If the temperature of a material is raised so high that electrons become stripped from atoms, what is formed?
a.	a gas	c.	a liquid	
b.	a plasma	d.	a solid	

ANS:	B	DIF:	Difficult	REF:	Box 1.1	
OBJ:	Understand modern concepts concerning the basic architecture of our Universe and its components.	MSC:	Applying

	8.	Which of the following bodies is the smallest?
a.	planet	c.	protoplanet	
b.	star	d.	planetesimal	

ANS:	D	DIF:	Moderate	REF:	1.4	
OBJ:	Understand modern concepts concerning the basic architecture of our Universe and its components.	MSC:	Analyzing

	9.	In the heliocentric model, ________.
a.	Earth orbits around the Sun	c.	Earth is a stationary planet	
b.	the Sun orbits around Earth	d.	all planets orbit Earth	

ANS:	A	DIF:	Easy	REF:	1.2	
OBJ:	Understand the character of our Solar System.	MSC:	Remembering

	10.	The Jovian planets are ________.
a.	Mars, Mercury, and Venus	c.	Jupiter, Saturn, Uranus, and Neptune	
b.	Mars, Venus, and Jupiter	d.	Mars and Saturn	

ANS:	C	DIF:	Easy	REF:	1.2	
OBJ:	Understand the character of our Solar System.	MSC:	Remembering

	11.	The Sun was created at the center of the accretionary disk when the temperature became high enough for ________ to occur.
a.	fusion	c.	combustion	
b.	fission	d.	radiation	

ANS:	A	DIF:	Easy	REF:	1.3	
OBJ:	Understand the character of our Solar System.	MSC:	Understanding

	12.	The planets orbit the Sun along the ________ plane.
a.	orbital	c.	ecliptic	
b.	concentric	d.	rotational	

ANS:	C	DIF:	Difficult	REF:	1.2	
OBJ:	Understand the character of our Solar System.	MSC:	Understanding

	13.	Terrestrial planets are mainly composed of ________ while Jovian planets are made dominantly of ________.
a.	volatiles; rock and metals	
b.	rock and metals; volatiles	
c.	refractory materials; volatiles and metals	
d.	volatiles and metals; refractory materials	

ANS:	B	DIF:	Easy	REF:	1.2	
OBJ:	Understand the character of our Solar System.	MSC:	Understanding

	14.	An important contribution made by Copernicus is his (correct) assertion that the ________.
a.	Earth is spherical	
b.	Sun is the center of the whole Universe	
c.	Sun is the center of Earth’s orbit	
d.	Earth is the center of the Universe	

ANS:	C	DIF:	Difficult	REF:	1.2	
OBJ:	Understand the character of our Solar System.	MSC:	Applying

	15.	The image below represents which model of the solar system?

a.	lunarcentric	c.	geocentric	
b.	electrocentric	d.	heliocentric	

ANS:	C	DIF:	Easy	REF:	1.2	
OBJ:	Understand the character of our Solar System.	MSC:	Applying

	16.	It is believed that our solar system resulted from a second- or third-generation nebula. How do we know this?
a.	The age of the Sun suggests this.	
b.	The size of the Sun suggests this.	
c.	The number of gas giants suggests this.	
d.	The mix of complex elements suggests this.	

ANS:	D	DIF:	Difficult	REF:	1.4	
OBJ:	Understand the character of our Solar System.	MSC:	Analyzing

	17.	The best estimate of when the Universe formed is ________.
a.	13.7 Ma	c.	4.57 Ma	
b.	13.8 Ga	d.	4.57 Ga	

ANS:	B	DIF:	Moderate	REF:	1.3	
OBJ:	Understand scientific explanations for the formation of the Universe and the Earth.
MSC:	Remembering		

	18.	The current estimate for the age of Earth of 4.57 Ga comes from ________.
a.	radiometric age dating of meteorites	
b.	radiometric age dating of sedimentary rocks	
c.	the light from distant galaxies	
d.	the amount of nuclear fuel in the Sun	

ANS:	A	DIF:	Moderate	REF:	1.4	
OBJ:	Understand scientific explanations for the formation of the Universe and the Earth.
MSC:	Remembering		

	19.	According to the Expanding Universe theory, our Universe is ________.
a.	expanding only	c.	not moving at all	
b.	contracting only	d.	contracting and expanding	

ANS:	A	DIF:	Easy	REF:	1.3	
OBJ:	Understand scientific explanations for the formation of the Universe and the Earth.
MSC:	Understanding		

	20.	Differentiation of the core from the mantle early in Earth’s history was possible because the planet was ________ at the time.
a.	very cold	c.	very small	
b.	very hot	d.	the only planet in the solar system	

ANS:	B	DIF:	Moderate	REF:	1.4	
OBJ:	Understand scientific explanations for the formation of the Universe and the Earth.
MSC:	Understanding		

	21.	The process of differentiation results in all of the following EXCEPT ________.
a.	denser materials becoming concentrated near the cores of planets	
b.	rocky material forming the mantles of planets	
c.	planets becoming approximately spherical	
d.	planets forming atmospheres	

ANS:	D	DIF:	Easy	REF:	1.4	
OBJ:	Understand scientific explanations for the formation of the Universe and the Earth.
MSC:	Applying

	22.	Which of the following images shows the formation of the Moon?

a.	A	c.	C	
b.	B	d.	D	

ANS:	C	DIF:	Difficult	REF:	1.5	
OBJ:	Understand scientific explanations for the formation of the Universe and the Earth.
MSC:	Applying

	23.	The age of the Universe is ________.
a.	less than the age of the Earth	c.	greater than the age of the Earth	
b.	the exact same age as the Earth	d.	impossible to determine	

ANS:	C	DIF:	Difficult	REF:	1.3	
OBJ:	Understand scientific explanations for the formation of the Universe and the Earth.
MSC:	Applying

	24.	According to the Big Bang theory, ________.
a.	Earth is much older than the rest of the Universe	
b.	the Universe is much older than Earth	
c.	Earth and the Universe formed at about the same time	
d.	there is no way of knowing how old the Universe might be	

ANS:	B	DIF:	Moderate	REF:	1.3	
OBJ:	Understand scientific explanations for the formation of the Universe and the Earth.
MSC:	Analyzing

	25.	The Earth’s magnetic field is a ________.
a.	monopole, as would be produced by just one pole of a magnet	
b.	dipole, such as that produced by a bar magnet	
c.	torus, a doughnut-shaped ring parallel to Earth’s equator	
d.	sphere, following the shape of Earth	

ANS:	B	DIF:	Easy	REF:	1.5	
OBJ:	Understand the overall character of the Earth’s magnetic field, atmosphere, and surface.
MSC:	Remembering		

	26.	Presently, Earth’s atmosphere is dominated by which two gases?
a.	hydrogen and helium	c.	nitrogen and oxygen	
b.	oxygen and carbon dioxide	d.	carbon dioxide and sulfur dioxide	

ANS:	C	DIF:	Easy	REF:	1.6	
OBJ:	Understand the overall character of the Earth’s magnetic field, atmosphere, and surface.
MSC:	Remembering		

	27.	The atmosphere is divided into several distinct layers. The layer we live in is called the ________.
a.	stratosphere	c.	troposphere	
b.	thermosphere	d.	mesosphere	

ANS:	C	DIF:	Moderate	REF:	1.6	
OBJ:	Understand the overall character of the Earth’s magnetic field, atmosphere, and surface.
MSC:	Remembering		

	28.	The image below shows Earth’s magnetic field. Earth’s magnetic field lines are distorted (i.e., not symmetrical) because ________.

a.	Earth is rapidly rotating around the Sun	
b.	Earth is rotating on an internal axis	
c.	convection is occurring in the outer core	
d.	solar wind deflects Earth’s magnetic field lines	

ANS:	D	DIF:	Moderate	REF:	1.5	
OBJ:	Understand the overall character of the Earth’s magnetic field, atmosphere, and surface.
MSC:	Understanding		

	29.	An aurora (shown below) is produced when ________.

a.	solar wind particles are directed toward the magnetic poles and excite atmospheric gases	
b.	swamp gases rise from the arctic tundra and react with the upper atmosphere	
c.	radiation in the Van Allen belts can be seen on a clear, cold night	
d.	lightning travels from cloud to cloud rather than cloud to ground	

ANS:	A	DIF:	Moderate	REF:	1.6	
OBJ:	Understand the overall character of the Earth’s magnetic field, atmosphere, and surface.
MSC:	Understanding		

	30.	If one were to ride a hot air balloon up into the atmosphere, one would experience the concentration of gases ________.
a.	becoming denser	
b.	becoming less dense	
c.	remaining the same	
d.	increasing for the first 10 kilometers, then starting to decline	

ANS:	B	DIF:	Moderate	REF:	1.6	
OBJ:	Understand the overall character of the Earth’s magnetic field, atmosphere, and surface.
MSC:	Applying

	31.	Volatile materials can exist as a gas at Earth’s surface. Which of the following is NOT a volatile material?
a.	water	c.	hydrogen	
b.	silicon	d.	carbon dioxide	

ANS:	B	DIF:	Moderate	REF:	1.6	
OBJ:	Understand the overall character of the Earth’s magnetic field, atmosphere, and surface.
MSC:	Applying

	32.	According to the image below, temperature increases within the stratosphere. Why is this?

a.	The stratosphere contains ozone, which absorbs radiation.	
b.	The stratosphere is closer to the Sun, thus receives more heat.	
c.	The heat from the troposphere rises into the stratosphere.	
d.	The increase in pressure warms gases within the stratosphere.	

ANS:	A	DIF:	Difficult	REF:	1.6	
OBJ:	Understand the overall character of the Earth’s magnetic field, atmosphere, and surface.
MSC:	Analyzing

	33.	The most common minerals within Earth are ________.
a.	silicates	c.	oxides	
b.	carbonates	d.	hydroxides	

ANS:	A	DIF:	Easy	REF:	1.6	
OBJ:	Understand the variety and composition of materials that make up our planet.
MSC:	Remembering		

	34.	Hot, liquid rock beneath Earth’s surface is termed ________.
a.	lava	c.	volatiles	
b.	magma	d.	mantle	

ANS:	B	DIF:	Easy	REF:	1.6	
OBJ:	Understand the variety and composition of materials that make up our planet.
MSC:	Remembering		

	35.	In the whole Earth, the four most common elements (by mass) are oxygen, silicon, magnesium, and ________.
a.	copper	c.	iron	
b.	lead	d.	zinc	

ANS:	C	DIF:	Moderate	REF:	1.6	
OBJ:	Understand the variety and composition of materials that make up our planet.
MSC:	Remembering		

	36.	Which of the following is NOT required for a substance to be considered a mineral?
a.	It must be solid.	
b.	It must be naturally occurring.	
c.	It must contain carbon.	
d.	It must have atoms arranged in an orderly pattern.	

ANS:	C	DIF:	Easy	REF:	1.6	
OBJ:	Understand the variety and composition of materials that make up our planet.
MSC:	Understanding		

	37.	Which of the following lists compositions in order of increasing silica content?
a.	felsic, intermediate, ultramafic, mafic	c.	felsic, intermediate, mafic, ultramafic	
b.	ultramafic, mafic, intermediate, felsic	d.	mafic, ultramafic, intermediate, felsic	

ANS:	B	DIF:	Difficult	REF:	1.6	
OBJ:	Understand the variety and composition of materials that make up our planet.
MSC:	Understanding		

	38.	Glass is different from a mineral because it ________.
a.	is not naturally occurring	
b.	is not a solid	
c.	does not have atoms arranged in an orderly pattern	
d.	contains carbon and is therefore organic	

ANS:	C	DIF:	Moderate	REF:	1.6	
OBJ:	Understand the variety and composition of materials that make up our planet.
MSC:	Understanding		

	39.	If you were measuring the elevation of a mountain, you would be measuring variation in ________, whereas if you were doing the same on a midocean ridge, you would be measuring variation in ________.
a.	bathymetry; topography	c.	topography; isostasy	
b.	bathymetry; isostasy	d.	topography; bathymetry	

ANS:	D	DIF:	Easy	REF:	1.6	
OBJ:	Understand the variety and composition of materials that make up our planet.
MSC:	Applying

	40.	The density of rocks is generally related to composition. Which of the following choices places rock compositions in order of increasing density?
a.	felsic, intermediate, ultramafic, mafic	c.	felsic, intermediate, mafic, ultramafic	
b.	ultramafic, mafic, intermediate, felsic	d.	mafic, ultramafic, intermediate, felsic	

ANS:	C	DIF:	Difficult	REF:	1.7	
OBJ:	Understand the variety and composition of materials that make up our planet.
MSC:	Applying

	41.	As compared to ultramafic rocks, mafic rocks have a ________.
a.	greater proportion of silica	
b.	lesser proportion of silica	
c.	greater proportion of iron and magnesium atoms	
d.	greater density	

ANS:	A	DIF:	Moderate	REF:	1.6	
OBJ:	Understand the variety and composition of materials that make up our planet.
MSC:	Applying

	42.	The densest layer of Earth is the ________.
a.	crust	c.	outer core	
b.	mantle	d.	inner core	

ANS:	D	DIF:	Easy	REF:	1.7	
OBJ:	Understand the nature of the Earth’s internal layering.	MSC:	Remembering

	43.	The lithosphere is composed of the ________.
a.	crust only	
b.	crust, mantle, and outer core	
c.	top 100 meters of sediments and sedimentary rocks	
d.	crust and the uppermost part of the mantle	

ANS:	D	DIF:	Moderate	REF:	1.8	
OBJ:	Understand the nature of the Earth’s internal layering.	MSC:	Remembering

	44.	The lithosphere lies directly above the ________.
a.	transition zone	c.	asthenosphere	
b.	crust	d.	lower mantle	

ANS:	C	DIF:	Easy	REF:	1.8	
OBJ:	Understand the nature of the Earth’s internal layering.	MSC:	Understanding

	45.	The distinction between the crust and the mantle is primarily on the basis of a difference in ________.
a.	composition	c.	ability to flow	
b.	color of minerals	d.	distance from the Sun	

ANS:	A	DIF:	Easy	REF:	1.8	
OBJ:	Understand the nature of the Earth’s internal layering.	MSC:	Understanding

	46.	In general, the mantle is made of the rock ________ and has a(n) ________ composition.
a.	granite; intermediate	c.	gabbro; mafic	
b.	basalt; mafic	d.	peridotite; ultramafic	

ANS:	D	DIF:	Moderate	REF:	1.8	
OBJ:	Understand the nature of the Earth’s internal layering.	MSC:	Understanding

	47.	From left to right, correctly label each section of this slice of Earth. Note that 1 starts at the surface of Earth and 6 ends at the center of Earth.

a.	crust, liquid outer core, transition zone, solid inner core, upper mantle, lower mantle	
b.	crust, upper mantle, transition zone, lower mantle, liquid outer core, solid inner core	
c.	crust, transition zone, upper mantle, lower mantle, liquid outer core, solid inner core	
d.	transition zone, crust, liquid outer core, solid inner core, upper mantle, lower mantle	

ANS:	B	DIF:	Moderate	REF:	1.8	
OBJ:	Understand the nature of the Earth’s internal layering.	MSC:	Applying

	48.	As compared to the asthenosphere, the lithosphere is ________.
a.	cooler and more able to flow	c.	cooler and less able to flow	
b.	hotter and more able to flow	d.	hotter and less able to flow	

ANS:	C	DIF:	Moderate	REF:	1.8	
OBJ:	Understand the nature of the Earth’s internal layering.	MSC:	Applying

	49.	During a journey to the center of Earth, one would experience temperature ________.
a.	and pressure both increasing	
b.	and pressure both decreasing	
c.	increasing but pressure staying nearly the same	
d.	remaining remarkably constant but pressure increasing	

ANS:	A	DIF:	Easy	REF:	1.7	
OBJ:	Understand the nature of the Earth’s internal layering.	MSC:	Applying

	50.	Which of the following statements about Earth’s core is FALSE?
a.	Its metallic content is likely similar to what has been found in metallic meteorites.	
b.	It is partly liquid and partly solid.	
c.	It is composed of an iron alloy (mostly iron with a few other metallic elements mixed in).	
d.	By volume, it is the largest compositional layer of Earth.	

ANS:	D	DIF:	Moderate	REF:	1.8	
OBJ:	Understand the nature of the Earth’s internal layering.	MSC:	Analyzing

SHORT ANSWER

	1.	Why was Pluto removed from the list of planets in our solar system?

ANS:	
Pluto has not cleared its orbit of all debris and thus no longer qualifies as a planet according to the new definition.

DIF:	Easy	REF:	1.2	OBJ:	Understand the character of our Solar System.
MSC:	Understanding		

	2.	Scientist have estimated the age of Earth to be 4.57 Ga. What did they use to determine this age and why did they use it?

ANS:	
The age of Earth was determined by radiometric age dating of meteorites. Rocks from Earth have been recycled so much that we no longer have any rocks that date back to the formation of Earth. However, since everything in the solar system was created at the same time, and meteorites have not been recycled since their formation, meteorite samples were used to determine the age of the solar system.

DIF:	Moderate	REF:	1.5	
OBJ:	Understand scientific explanations for the formation of the Universe and the Earth.
MSC:	Analyzing

	3.	Where does Earth’s magnetic field originate and what is the primary benefit of the magnetic field to life on Earth?

ANS:	
Earth’s magnetic field is created in convection in the liquid outer core. The magnetic field protects Earth by deflecting charged particles from the Sun.

DIF:	Moderate	REF:	1.5	
OBJ:	Understand the overall character of the Earth’s magnetic field, atmosphere, and surface.
MSC:	Understanding		

	4.	What is the difference between a mineral and a glass?

ANS:	
A mineral contains atoms arranged in an ordered pattern, whereas glass contains no such internal organization.

DIF:	Easy	REF:	1.6	
OBJ:	Understand the variety and composition of materials that make up our planet.
MSC:	Analyzing

	5.	Draw a cross-section of Earth showing its layers. Label the layers and list the average composition of the layers.

ANS:	

DIF:	Easy	REF:	1.8	
OBJ:	Understand the nature of the Earth’s internal layering.	MSC:	Understanding