ESS 101 EXAM 1 Review 2026/2027 |
Complete Practice Questions & Answers |
Certification Study Guide
nebular hypothesis - correct answer-1. supernova and formation of primordial
dust cloud
2. condensation of primordial dust forms disk shaped nebular cloud rotating
counter-clockwise.
3. proto sun and planets begin to form
4. accretion of planetesimals and differentiation of planets and moons (4-6 billion
years ago).
5. existing solar system takes shape.
Evidence of nebular hypotheses - correct answer-1. Planets and moons revolve in
a counter-clockwise direction (not random)
2. almost all planets and moons rotate on their axis in a counter-clockwise
direction.
3. planetary orbits are aligned along the suns equatorial plane (not randomly
organized)
4. observations from Hubble telescope and radio astronomy indicate that other
planetary systems are forming from condensed nebular dust.
,Terrestrial Planets - correct answer-Close to the sun, dense, small/rocky, silicate
minerals, metallic cores
Twelve earths would fit across the diameter of Jupiter.
Jovian Planets - correct answer-Far from the sun, low density, large, gaseous
(hydrogen, methane)
Why does the earth and terrestrial planets have so little molecular hydrogen
comprising their respective atmosphere, yet the primordial dust cloud was mostly
comprised of hydrogen gas? - correct answer-Hydrogen gas and helium gas
escapes to space when put in our atmosphere.
Jupiter, saturn, and neptune maintain molecular hydrogen gas in the atmosphere
because they have high density.
Differentiated Earth - correct answer-1. Iron Nickel Core (outer core liquid)
(inner core solid)
2. Fe-Mg silicate mantle
3. Fe-Mg-Al Silicate Crust (Ocean and Continental)
4. Oceans
5. atmosphere
How is the earth compositionally zoned? - correct answer-Along a density
gradient
How did the earth become compositionally zoned? - correct answer-1. Accretion
of planetesimals
,2. initial heating due to kinetic energy of colliding planetesimals and
compressional heating.
3. additional heating from radioactive decay.
4. iron catastrophe: melting temp of iron reached and dense iron nickel sink to
core and lighter materials are displaced outwards (including silicate rock of
mantle and crust, ocean waters and atmospheric gases)
5. earth becomes compositionally zoned based on density (densest iron nickel in
core-least dense materials comprise the atmosphere) 500 mil yrs after the initial
accretion process.
6. convective overturn in asthenosphere, mantle and outer core still occur today.
Why did the earth heat up and then rapidly cool during the differentiation
process? - correct answer-When earth was solid-heat gain was greater than the
heat lost to space. This means that the internal temperature rises until it
exceeded the melting temp of oxygen and nitrogen until exceeded iron nickel
catastrophe. Earth is completely molten and then compositionally zoned.
When earth was liquid- convection-hot gas rises , after it became molten, the
earth rapidly cooled off and solidified.
Why does earth possess little evidence of its early accretion history? - correct
answer-Because of weathering, plate tectonics, moon has no atmosphere and
biosphere.
Emissions from degassing of the earth during its differentiation. - correct answer-
h2o, co2, h2, he, n2
Where did molecular H and He escape to? - correct answer-space
, When did oxygenation of the atmosphere occur? - correct answer-later following
evolution of marine algae and plants that use photosynthesis to convert co2 to o2
as a part of their life processes.
What layers of the earth can be directly observed? - correct answer-crust and
uppermost mantle.
Evidence of initial composition of the solid earth based on meteorite studies.
There are two major classes of meteorites that dominate collected samples.
Carbon based meteorites are much rarer, but indicate that the prescursor of life
was present early on. - correct answer-1. Metallic meteorites (iron nickel density
9.0-10 gm/cm3)
2. chondritic meteorites: Fe-Mg silicate, rocky, density is 3.0-3.3)
3. carbonaceous chondrites (rare)
What is earths average density? - correct answer-5.5 g/cm3
How can average density of earth be inferred? - correct answer-Based on
gravitational properties and its effect on known masses such as orbiting satellites.
Density of earths crust? - correct answer-2.6-3 g/cm3
density of uppermost mantle? - correct answer-3.0-3.3 g/cm3
Based on the density information, what can you infer about the density of the
lower mantle and the earths core? - correct answer-Density must be higher than
the average.
Complete Practice Questions & Answers |
Certification Study Guide
nebular hypothesis - correct answer-1. supernova and formation of primordial
dust cloud
2. condensation of primordial dust forms disk shaped nebular cloud rotating
counter-clockwise.
3. proto sun and planets begin to form
4. accretion of planetesimals and differentiation of planets and moons (4-6 billion
years ago).
5. existing solar system takes shape.
Evidence of nebular hypotheses - correct answer-1. Planets and moons revolve in
a counter-clockwise direction (not random)
2. almost all planets and moons rotate on their axis in a counter-clockwise
direction.
3. planetary orbits are aligned along the suns equatorial plane (not randomly
organized)
4. observations from Hubble telescope and radio astronomy indicate that other
planetary systems are forming from condensed nebular dust.
,Terrestrial Planets - correct answer-Close to the sun, dense, small/rocky, silicate
minerals, metallic cores
Twelve earths would fit across the diameter of Jupiter.
Jovian Planets - correct answer-Far from the sun, low density, large, gaseous
(hydrogen, methane)
Why does the earth and terrestrial planets have so little molecular hydrogen
comprising their respective atmosphere, yet the primordial dust cloud was mostly
comprised of hydrogen gas? - correct answer-Hydrogen gas and helium gas
escapes to space when put in our atmosphere.
Jupiter, saturn, and neptune maintain molecular hydrogen gas in the atmosphere
because they have high density.
Differentiated Earth - correct answer-1. Iron Nickel Core (outer core liquid)
(inner core solid)
2. Fe-Mg silicate mantle
3. Fe-Mg-Al Silicate Crust (Ocean and Continental)
4. Oceans
5. atmosphere
How is the earth compositionally zoned? - correct answer-Along a density
gradient
How did the earth become compositionally zoned? - correct answer-1. Accretion
of planetesimals
,2. initial heating due to kinetic energy of colliding planetesimals and
compressional heating.
3. additional heating from radioactive decay.
4. iron catastrophe: melting temp of iron reached and dense iron nickel sink to
core and lighter materials are displaced outwards (including silicate rock of
mantle and crust, ocean waters and atmospheric gases)
5. earth becomes compositionally zoned based on density (densest iron nickel in
core-least dense materials comprise the atmosphere) 500 mil yrs after the initial
accretion process.
6. convective overturn in asthenosphere, mantle and outer core still occur today.
Why did the earth heat up and then rapidly cool during the differentiation
process? - correct answer-When earth was solid-heat gain was greater than the
heat lost to space. This means that the internal temperature rises until it
exceeded the melting temp of oxygen and nitrogen until exceeded iron nickel
catastrophe. Earth is completely molten and then compositionally zoned.
When earth was liquid- convection-hot gas rises , after it became molten, the
earth rapidly cooled off and solidified.
Why does earth possess little evidence of its early accretion history? - correct
answer-Because of weathering, plate tectonics, moon has no atmosphere and
biosphere.
Emissions from degassing of the earth during its differentiation. - correct answer-
h2o, co2, h2, he, n2
Where did molecular H and He escape to? - correct answer-space
, When did oxygenation of the atmosphere occur? - correct answer-later following
evolution of marine algae and plants that use photosynthesis to convert co2 to o2
as a part of their life processes.
What layers of the earth can be directly observed? - correct answer-crust and
uppermost mantle.
Evidence of initial composition of the solid earth based on meteorite studies.
There are two major classes of meteorites that dominate collected samples.
Carbon based meteorites are much rarer, but indicate that the prescursor of life
was present early on. - correct answer-1. Metallic meteorites (iron nickel density
9.0-10 gm/cm3)
2. chondritic meteorites: Fe-Mg silicate, rocky, density is 3.0-3.3)
3. carbonaceous chondrites (rare)
What is earths average density? - correct answer-5.5 g/cm3
How can average density of earth be inferred? - correct answer-Based on
gravitational properties and its effect on known masses such as orbiting satellites.
Density of earths crust? - correct answer-2.6-3 g/cm3
density of uppermost mantle? - correct answer-3.0-3.3 g/cm3
Based on the density information, what can you infer about the density of the
lower mantle and the earths core? - correct answer-Density must be higher than
the average.
