Final Exam: Physical Science
Objects – seen or touched
Properties- qualities or attributes characteristic of an object
Referents- comparative properties ex. Sky blue
Know the matches
Area = LW
Volume = LWH
Theory
- Based set of working hypotheses
- Based upon considerable experimental support
- From the framework of thought and experiment
Velocity (m/s)
Acceleration
- Result in a change of motion
Falling Objects
- Free fall – falling under the influence of gravity without air resistance.
- Acceleration same for all objects
Newton’s 1st Law of Motion
- Inertia (resists to change in motion)
- Every object retains in rest unless acted upon by an unbalanced force.
Newton’s Law of Gravitation
- Attractive force between all objects everywhere
- G= 9.8m/s^2
Weightlessness
- Moon (mass stays the same, weight decreases)
- W=mg (weight is a force)
Energy sources today
- Petroleum (37%)
- Natural Gas (25%)
- Coal (21%)
- Nuclear (9%)
- Renewable (8%)
Waves
- Longitudinal Wave (straight)
- Transverse Wave (up & down)
Vibrations
- Amplitude- max extent of displacement from equilibrium
- Frequency- number of cycles per second (units = hertz, Hz)
- Period and frequency are inversely related.
- Human hearing range: 20 Hz
Properties of Light
- Light acts as a wave and a phototn
Nuclear Atom
- Atomic number
o Number of protons in nucleus
o Elements distinguished by atomic number
o 113 elements identified
o Number of protons=number of electrons in neutral atoms
- Isotopes
o Same number of protons; different number of neutrons
Metals, Nonmetals, & Semiconductors
- Noble gases – filled shells, inert
- 1-2-3 outer electrons
o Lose to become positive ions
o Metals
- 5-7 outer electrons
o Tend to gain electrons and form negative ions
o Nonmetals
Chemical Bonds
- Three types
o Ionic
§ Electrons transferred between atoms
§ Electrostatic force=binding force
Multiple Bonds
- Sharing of more than one electron pair
- Ex.
o Ethylene – double bond
o Acetylene – triple bond
Balancing Equations
- Mass of reactants = mass of products
- Law of conservation of mass- atoms are neither created nor destroyed in chemical reactions.
Household water
- Lawn and garden (29%)
- Toilets (29%)
- Bathing (23%)
- Laundry (11%)
- Cleaning dishes (6%)
- Drinking and cooking (2%)
Ionic Compound Formulas
- Two rules
o Write the symbol for the positive ion first followed by the negative ion symbol.
o Assign subscripts to ensure the compound is electrically neutral.
Covalent Compound Names
- Molecular – composed of 2 or more nonmetals.
- The same elements can combine to form different compounds.
- Two rules
o The first element in the formula is named with # indicated by a Greek prefix if greater than 1
o Stem name of second element next; Greek prefix for number; ending in “-ide”
Stepwise Balancing Procedure
Formula Weight
- M = m/n
o M = molar mass
o m = mass of a substance (in grams)
o n = number of moles of a substance
Avogrados Number
- 6.022 × 10²³
Calorie
- An energy unit equal to the approximate amount of energy required to raise one gram of water by one degree Celsius, or about 4.2 joules.
Visible light
- The color we see is a result of which wavelengths are reflected back to our eyes.
Stars
- Massive, dense balls of incandescent gas
- Powered by fusion reactions in their core
- Hydrogen to Helium
Evidence of Earth’s Internal Structure
- Earth’s magnetic field
- Gravity effects
- Heat flow
- Vibrations in the Earth
o Seismic waves
o Radiate outward from earthquakes.
o Also noted from nuclear explosions.
Earth’s Internal Structure
- Three main zones
- Crust
o Outer thin Shell
o Mantle
§ Much thicker than the crust
o Core
§ Central part
Theory of Plate Tectonics
- Wegener’s continental drift hypothesis
o Evidence used by Wegener
§ Fit of south America and Africa
§ Fossils match across the seas
§ Rock types and structures match
§ Ancient climates
o The main objection to Wegener’s proposal was its inability to provide a mechanism.
History of Earth’s Interior
- Differentiation
o Melting and gravitational settling of heavier elements
o Gave Earth its presented stratified structure.
History of Earth’s Interior
- Earth formed approximately 4.6 billion years ago in the solar nebula.
The crust
- Covers entire earth
- Oceanic crust
o Much thinner
o Basaltic rock, denser
- Continental crust
o Granite rock, less dense
A More Detailed Structure
- Asthenosphere
o Thin, hot, elastic semi-liquid layer in the upper mantle
- Lithosphere
o The solid layer above the asthenosphere
Divergent Boundaries
- Occur between two plates moving away from each other
- Molten material from the mantle rises to fill fissures.
- New crust zone
- Often accompanied by volcanic activity and earthquakes.
- Ex: Mid-Atlantic ridge
Convergent Boundaries
- Occurs when two plates move toward each other
- Old crust destroyed in the process
- Subduction zone
o Belt with the denser crust subducting under the other
o Subducted material partially melts
o Ex: Andes Mountains
Ocean-Continent Plate Convergence
- An oceanic plate of denser basaltic material subducted under less dense granite-type continental shelf.
- Marked by oceanic trenches, deep-seated earthquakes, and volcanic mountains.
Stress and Strain
- Force tending to compress, pull apart, or deform a rock
- 3 stress forces
o Compressive stress
§ Plates moving together
o Tensional stress
§ Plates moving apart
o Shear stress
§ Plates sliding past each other
Folding
- Folds
o Bends in layered bedrock
o Anticline: arch-shaped structure
o Syncline: trough-shaped
Classes of Faults
- Normal fault
o Footwall up
o hanging wall down
Other Faults
- reverse fault
o hanging wall moved upward footwall moves down
o result of horizontal compressive stress
- Thrust fault
o Reverse fault with a low-angle fault plane
- Faults provide information on the stresses producing the formation
Earthquakes
- Most occur along the fault planes when one side is displaced with respect to the other.
Seismic Waves
- P-wave
o Longitudinal
o Fastest waves
o Move through surface rocks and interior solid and liquid materials
- S-wave
o Transverse (Shear) wave
o Second fastest
o Do not travel through liquids
The Mantle
- Composed mainly of olivine
Other Core Evidence
- Earth’s Magnetic field
o The source is turbulent flow within the liquid core
o Material must conduct electricity
Present-day Understandings
- What drives the plates?
- Current working
o Hypothesis: convective cells in the asthenosphere
§ Hot fluid materials rise at diverging boundaries
§ Some escapes to form a new crust
§ The remainder spreads beneath the lithosphere, dragging overlaying plates with it
§ Convection
Interpreting Earth’s Surface
- Principle of uniformitarianism
o “The present is the Key to the past”
o Rocks are changed today by the same processes that changed them in the past
Causes of Earthquakes
- Elastic rebound theory
o Two plates press tightly together
o Friction restricts motion
o Stress builds until friction or rock rupture strength is overcome
o Stressed rock snaps suddenly into new position
o Stress
o Rupture
o Rebound
Classification of Earthquakes
- Based upon the depth of focus
1. Shallow-focus earthquakes
o 85% of all earthquakes
2. Intermediate-focus earthquakes
o 70 to 300 km deep
3. Deep-focus earthquakes
o About 3% of all earthquakes
Folded and Faulted Mountains
- Domed mountains
o Begin as a broad arching fold
o Overlaying sedimentary rocks weather away, leaving more resistant granite peaks
o The oldest rock is at the center
Origin of Mountains
- Mountains
o Elevated parts of the earth’s crust rising abruptly above the surrounding surface
o Created by folding and faulting of crust
o Three basic origins
1. Folding
2. Faulting
3. Volcanic Activity
Other Features
- Batholith
o A large amount of crystalized magma
o Stock: small protrusion from a batholith
o Batholith: intrusions can cause hogbacks
- Dike cut across rock layer
- Sill intrusion along the bedding plane
- UNDERSTAND IGNEOUS INTRUSION IN THE IMAGE
Tsunamis
- Ocean Waves created by earthquakes
- Physical characteristics
o Wave heights up to 0.5m in deep ocean can reach over 8m (26ft) in shallow water
Types of Volcanoes
- Shield volcano
o Constructed of solidified lava flows
o Broad, gently sloping cones
- Cider cone volcano
o Constructed of rock fragments (cinders)
o Steeper and smaller than shield volcanoes
- Composite volcano
o Alternating layers of cinders, ash and lava flows with volcanic mud
More Principles
- Principle of crosscutting relationships
o Any geologic feature that cuts across or intrudes into a rock mass must be younger than the rock mass
o This also applies to faults and folds
- Uniformitarianism- the present is the key to the past
Shifting Erosion and Deposition Sited
- Erosion and deposition processes very over time and location
- Unconformity
o A time break in the rock record
o Cause by erosion or nondeposition
Weathering
- Slow changes resulting in the breakup, crumbling and other destruction of solid rock
- Includes physical, chemical, and biological processes
- Dependent on the type of rock and the attitude
- Contributes to
1. the rock cycle
2. formation of soils
3. movement of rock materials over the earth’s surface
- Erosion
o The process of physically removing weathered materials
Mechanical Weathering
- The physical breakup of rocks without chemical change
- Disintegration processes
o Wedging
§ By frost
§ By trees
o Exfoliation
§ Reduced pressure effect
§ Fractures caused by expansion of underlying rock
Chemical Weathering
- Decomposition of minerals by chemical reactions
1. Oxidation
o Reactions with oxygen
o Produces red iron oxides
2. Carbonation
o Reactions with carbonic acid (carbon dioxide dissolved in water)
o Easily dissolves limestone
3. Hydration
o Reactions with water
o Includes dissolving in water and combining with water
Running Water
- Three streams transport mechanisms
1. Dissolved materials
2. Suspended materials
3. Rolling, bouncing, and sliding along stream bed
- Streambed evolves over time
Stream Development
- Youth
o Landmass recently uplifted
o Steep gradient, V-shaped valley w/o floodplain
- Maturity
o Stream gradient smoothed and lowered
- Old age
o Very low gradient
Geologic Time Scale
- Precambrian
o The time before life appeared
o 85% of Earth’s total time
Arranging Events in Order
- Principle of original horizontality
o This applies to sedimentary rocks
o On a large scale, sediments are deposited in flat-lying layers
o Any non-horizontal layers have been subjected to deformation forces.
Correlation
- Index fossils
o Distinctive and widely distributed plant or animal fossils
o Lived only briefly with a common extinction time
o Allow correlations between ages of exposed rock in different locations
- Relative dating technique
- Why do we use relative dating?
Geologic Periods and Typical Fossils – Mesozoic era
- Triassic Period
o First dinosaurs
o First mammals
o First modern gymnosperms
o THERE HAVE BEEN 5 MASS EXTINCTIONS
Fossils
- Any evidence of former life
o Can include actual or altered remains of plants and animals
o Also less direct evidence such as leaf imprints, dinosaur footprints, and bat droppings
Types of Fossilization
- Common formation processes
1. Preservation or alteration of hard parts
o Shells, bones, teeth, pollen, and spores
2. Preservation of shape
3. Preservation of signs of activity
- Soft parts are rarely found
o Often protected by ice, resin, or tar
Shape Preservation
- Molds
o The original organism dissolved, leaving a void
- Casts
o Original organism dissolved
o Sediment deposited into the void.
- Petrified fossils
1. Mineralization
o Pore spaces filled with minerals
2. Replacement
o The original material dissolved and was replaced by new materials
- Petrified wood formed by both processes
Preserved Activities of Organisms
- Footprints
- Tunnels of burrowing animals
- Dinosaur nests
- Eggs
o Usually involve mud or other soft substrates subsequently covered with silt or volcanic ash.
Geologic Time
- Modern techniques
o Determines the age of rocks by measuring the radioactive decay of unstable elements.
Interpreting Geologic History
1. Time periods are extremely long
o Life goes back at least 3.5 billion years
2. The earth has changed greatly over its history
o Warming, cooling; sea level changes; continental drift
3. Many periods of mass extinction have passed
o Most took millions of years
Groundwater Deposits
- Zone of saturation
o Collected groundwater above an impermeable layer
o Water table
§ The top boundary of the zone of saturation
o Water can move laterally within the zone of saturation
- Aquifer
o A subsurface layer of highly permeable material capable of producing water.
o Artesian aquifer
§ Confined under pressure from water at a higher elevation
Ground Water Flow
- Sand and gravel
o Open pore spaces
o Permeable to water flow
- Clay
o Low porosity
o Impermeable when saturated or compressed
Surface Water
- Collectively the water in streams, ponds, lakes, and reservoirs
- Watershed
o Land area drained by a stream or streams
o Two adjacent watersheds separated by a divide
o Continental divide separates watersheds draining into opposite sides of a continent.
Minerals
- Earth science definition: a naturally occurring, inorganic solid element or compound with a crystalline structure.
o Cannot be synthetic
o Not directly produced by a living organism
o Must have regular, repeating pattern
o Ex: halite (NaCl)
Minerals: The Building Blocks of Rocks
- Definition of a mineral
o Natural
o Inorganic
o Solid
o Possess an orderly internal structure of atoms
o Have a definite chemical composition
- Rock – any naturally occurring solid mass of mineral or mineral-like matter
Physical Properties of Minerals
- Cleavage
o Tendency to break along planes of weak bonding
o Produces flat, shiny surfaces
Birth of modern astronomy
- Nicolaus Copernicus (1473-1543)
o Concluded Earth was a planet
o Constructed a model of the solar system that put the sun at the center, but he used circular orbits for the planets
Two most abundant elements of the earth’s surface? Oxygen & silica
Where is the following is not? …. (what is Earth’s magnetic)
4.6 billion Earth’s age & solar system
Correctly label the earth’s internal structure
Wegner’s (maybe a “what is not” question)
Earth’s materials
Differentiation
Divergent boundaries youngest crust on earth: divergent boundary
Convergent boundary: oceanic and continental
What heat moves a plate: convection
3 types of stress that they deal with
Folding
Faults
Circum – pacific – known as ring of fire
Tsunamis are created by earthquakes.
Unconformity- a break in time
What is the following weathering: the attitude of the rock
Mineral not organic
Label: groundwater Deposits A, b, c