Geology 102- Quiz 1

measurement of an iron atom

.000000126 m

diameter of Earth

12,700,000m/12,700km

lightyear

distance light travels in a year; 9,461,000,000,000,000 m

speed of sound

1,000 km/hr

speed of light

1×10⁹km/hr

big and small #s

what is scientific notation used for?

equation for force

force=mass x gravity

bpt of water

373K, 100ºC, 212ºF

fpt of water

273K, 0ºC, 32ºF

temp of no molecular motion

0K, -273ºC, -460ºF

protons

determine element; 1 amu

electrons

determines charge; 1/1842 amu

cations

positively charged electrons; has extra e^-

anions

negatively charged electrons; does not have enough e^-

neutrons

protons + this = mass; 1 amu

noble gases

doesn't combine with anything due to the right amount of p and e^-

scientific measurement for distance

m

scientific measurement for mass

kg

scientific measurement for time

seconds

scientific measurement for temp

K

scientific measurement for electric current

amperes

scientific measurement for luminosity

candelas

scientific measurement for amount of material

moles

scientific measurement for energy

Joules

scientific measurement for angles

radians

scientific measurement for anglar area

stradians (radians²)

T

tetra; 10¹²

G

giga; 10⁹

M

mega; 10⁶

k

kilo; 10³

m

milli; 10^-3

µ

micro; 10^-6

n

nano; 10^-9

p

pico; 10^-12

atom

based on # of protons

isotope

mass

relationship between atomic # and abundance

the lower the atomic #, the higher the abundance in solar system

2 most abundant elements in sun and universe

H and He

atoms with even # p's

more isotopes

atoms with even # n's

more abundance

wavelength

1 wave/sec=1 Hertz

constant for speed of light

c

refractive index

N or RI; speed in vacuum÷speed in material;always greater than 1 since light is the fastest in vacuum

property dispersion

slower speed=higher RI

parallel solid objects

undoes light

non-parallel solid objects

accentuates light; leads to spectrum due to bending wavelegnths

Fraunhofer lines

fine lights with no color appearing

elements in a spectrum

different frequencies and different wavelenghts absorbed

Hubble

Big Bang theory; looked at correlation between distance to different objects/galaxies and speed

how to tell how fast a galaxy goes

see absorption lines in spectrum of elements of our sun compared to other galaxies; (in others) H and He lines are shifted; Doppler Effec

Doppler Effect

if a galaxy is approaching you, light will compress (blue-ish); if it is going away from you in decompresses (red-ish); wavelength behind objects increase and in front of objects decrease

parallax

watching slight change of angle of a foreground (near) star on different days; used to measure distance

percentage of stars that vary in luminosity

10

clusters

stars within a galaxy (and galaxies within a universe) appear like this; further the ___, the average diameter will be smaller

closer stars

variable (10%) and period stars

farther stars

clusters

Big Bang

“superexplosion"; 1) most galaxies are moving away from us, not stars 2) distant galaxies are moving the fastest 3) distance÷speed=time → happened 13.8 Ga) 4) H 76% He 24% 5) background radiation

variable stars

when intensity varies over time, speed in which it happens varies; far stars are less luminous (and vice versa)

background radiation

natural radiation that is present in an environment

3 points of the nebular hypothesis of the solar system formation

1) cloud of interstellar dust was 20 atoms/cm³ 2) nearby supernova occured and the shosupernovackwave increased the density 3) due to the initial spin of cloud, it collects on itself and created planets

supernova

star reaches critical state in which it explodes

inner planets/terrestrial planets

mercury, venus, earth and mars

outer/jovian planets

jupiter, saturn uranus, neptune

gas giants

jupiter and saturn

ice giants

uranus and neptune

mass of Jupiter

77% of total mass of planets

mass of Sun

99.8% of total mass of our solar system

age of the solar system

4.56 billion years old; dated using primitive meteorites

E=mc²

E=energy, m=mass during a nuclear reaction, c=speed of light

2 reasons mass does not always equal #p+#n

1) atomic mass is the average of all isotopes 2) p and n weigh slieghtly different in different elements

why is ⁵⁶Fe the most stable element

lowest mass per nucleon

elements between 1-56

can release energy through fusion

elements above 56

needs energy to be stable through fission

fusion

combining smaller atoms with neutrons; releases energy for atoms below ⁵⁶Fe; spontaneous; 4¹H atoms combine to make ⁴He atoms; basic for H bombs; source of sun’s energy and possible future fusion of energy

fission

splitting bigger atoms into smaller ones; releases energy for atoms above ⁵⁶Fe; minimum mass per AMU and minimum energy occur at ⁵⁶Fe; basic for A bombs; all current nuclear power generation

reason as to why e=mc² works

energy (Joules), mass (kg) and speed of light (m/sec) are all intertwined

isotopic age dating that works to date the Earth

-²³⁵U → ²⁰⁶Pb + 8 alpha particles

-²³⁵U →²⁰⁷Pb + 7 alpha particles

-²³²Th →²⁰⁶Pb + 6 alpha particles

-⁸⁷Rb → ⁸⁷Sr (uncommonly used)

isotopic age dating that does not work to date the Earth

-⁴⁹K → ⁴⁰Ar

-isotopes of K bombard Ar isotopes with e^- flux

-⁴⁰Ar is a contaminate

-¹⁴C → ¹⁴N

-most common dating technique for things below 60ka

-formed in upper atmosphere

relationship between luminosity and temp

as temperature increases, so does luminosity

supergiants

low temperature, high luminosity

giants

mid temperature and luminosity

main sequence stars

high temperature, low luminosity; mass increases as temp rises, contains most stars; shows lifespan bc bigger stars are the hottest and brightest with the lowest lifespan

white dwarfs

high temperature, SUPER low luminosity

how to measure mass of a star

binary orbits

when the sun first formed

1) sun initially wasn’t hot enough for H burning; so it preformed Li burning (T-Tauri event) 2) as the sun gets hotter, it starts to combine ⁴He atoms to make ¹²C (helium burning)

why inner planets so different than outer planets

T-Tauri event was very powerful; gas and ice giants sucked elements from inner planet and was blasted farther from the sun

Red Giant

6-10 solar masses; bigger stars can do more burning which eventually makes them a Red Giant; preforms carbon burning (makes Na and Ne) and neon burning (makes O and Mg)

15+ SM star

3Bº but can still hold together; preforms silicone burning/E-process (makes Cr, Mn, Fe, Co, Nr); builds up without a supernova occuring

neutron star

solid mass of pure neutron

how is a neutron star created

SM with multiple elements burn with a core that contains Fe; so much Fe that it becomes very hot and it collapses in on itself (volume becomes massively smaller and explodes-supernova)

end result of a super nova

black hole; >20 SM

three kinds of fusion

S, R and P Process

S process

“slow process”; adding neutrons to an element where C is already burning; 1 per 1000 years; occurs in normal stars

R process

“rapid process”; occurs in supernovas and red giants as neutrons are moving rapidly; creates even more elements

P process

bombarding things with protons instead of neutrons; discovery still in progress; used by red giants

X process

unknown process; forms Li, Be and B

percentage of elements that are found in main sequence stars

99.9% (rest are found in red giants and supernovas)

most abundant element in core

Fe and Ni

most abundant element in the mantle and the crust

oxygen

nucleogenesis

heavier elements formed elements between carbon and Iodine by nuclear fusion