ACING EAPS 100 WITH ESSENTIAL A+ QUESTIONS AND
ANSWERS
How did the universe form?
The Big Bang Theory: 1920 Georges Lematre - Universe was originally inn a super
massive state that expanded rapidly in all different directions
How did the solar system form?
Nebular Hypothesis - 4.6 billion years ago a molecular cloud of gas (filled with particles
like ice, dust and rocks) collapsed and eventually they turned into stars and they heated
up
Terrestrial Planets
planetesimals made of rocks and metal, large iron core, too small to capture any
amount of hydrogen/ helium gas in solar nebula
Jovian Planets
formed far from sun, frozen gas small iron cores
How did Earth become differentiated?
The differentiation was caused by heavy metals (iron, nickel, etc.) that became the core
of the earth. The light elements (oxygen, silicon, etc) became the mantel and the crust
of the outer enriched layer
Heat: meteorite bombardment (heat to exterior) and radioactive decay of isotopes (heat
to deep interior),
Partial melting: the young Earth had to partially melt since solid materials are immobile.
Differential buoyancy: heavy metals sank to the interior while buoyant light elements
rose toward surface.
How do mineral abundances differ between the layers?
Inner core: mostly solid iron
Outer core: mostly liquid iron
, Mantle: Solid Fe/Mg silicates (iron/magnesium)
Oceanic crust: solid k/Na silicates (potassium/sodium)
Continental crust: hydrosphere and atmosphere
What is relative geologic age-dating?
science of determining the order of past events without determining their exact age-you
can use estimated age instead
Place rocks in the sequence that they were formed starting from oldest to youngest.
Relationship between individual rock layers and other object. (fossil assembly)
What is absolute geologic age-dating?
process of determining the order of events with a specific age on a time scale
Perform absolute age dating using isotopes by its half-life. Provides an absolute
number.
What is the definition of "half-life" in regards to radiometric isotope?
The time it takes for one-half of the atoms of a radioactive material to disintegrate. It can
range from microseconds to billions of years
Parent decay half-life
1 half-life = 1/2 nuclei
2 half-life = 1/4 remains
3 half-life = 1/8 remains
5 half-life = 1/32 remains
6 half-life = 1/64 remains
Daughter accumulates
ANSWERS
How did the universe form?
The Big Bang Theory: 1920 Georges Lematre - Universe was originally inn a super
massive state that expanded rapidly in all different directions
How did the solar system form?
Nebular Hypothesis - 4.6 billion years ago a molecular cloud of gas (filled with particles
like ice, dust and rocks) collapsed and eventually they turned into stars and they heated
up
Terrestrial Planets
planetesimals made of rocks and metal, large iron core, too small to capture any
amount of hydrogen/ helium gas in solar nebula
Jovian Planets
formed far from sun, frozen gas small iron cores
How did Earth become differentiated?
The differentiation was caused by heavy metals (iron, nickel, etc.) that became the core
of the earth. The light elements (oxygen, silicon, etc) became the mantel and the crust
of the outer enriched layer
Heat: meteorite bombardment (heat to exterior) and radioactive decay of isotopes (heat
to deep interior),
Partial melting: the young Earth had to partially melt since solid materials are immobile.
Differential buoyancy: heavy metals sank to the interior while buoyant light elements
rose toward surface.
How do mineral abundances differ between the layers?
Inner core: mostly solid iron
Outer core: mostly liquid iron
, Mantle: Solid Fe/Mg silicates (iron/magnesium)
Oceanic crust: solid k/Na silicates (potassium/sodium)
Continental crust: hydrosphere and atmosphere
What is relative geologic age-dating?
science of determining the order of past events without determining their exact age-you
can use estimated age instead
Place rocks in the sequence that they were formed starting from oldest to youngest.
Relationship between individual rock layers and other object. (fossil assembly)
What is absolute geologic age-dating?
process of determining the order of events with a specific age on a time scale
Perform absolute age dating using isotopes by its half-life. Provides an absolute
number.
What is the definition of "half-life" in regards to radiometric isotope?
The time it takes for one-half of the atoms of a radioactive material to disintegrate. It can
range from microseconds to billions of years
Parent decay half-life
1 half-life = 1/2 nuclei
2 half-life = 1/4 remains
3 half-life = 1/8 remains
5 half-life = 1/32 remains
6 half-life = 1/64 remains
Daughter accumulates
