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118 terms

Science Midterm Review

I'm just giving this to y'all..
STUDY
PLAY
theory
explanation of things or events that is based on knowledge gained from many observations and experiments
science
systematic way of learning more about the natural world that provides possible explanations to questions and involves using a collection of skills
scientific theory
a possible explanation for repeatedly observed patterns in nature supported by observations and results from many investigations
scientific law
a rule that describes a pattern in nature but does not try to explain why something happens
system
a set of objects or parts that form a whole
life science
study of living systems and how they interact
Earth science
study of Earth systems and systems in space, including weather and climate systems, and the study of nonliving things such as rocks, oceans, and planets
physical science
study of matter, which is anything that takes up space and has mass, and the study of energy, which is the ability to cause changes
technology
use of science to help people in some way
observation
a record of description of an occurrence or pattern in nature
hypothesis
reasonable guess that can be tested and is based on what is known and what is observed
infer
to draw a conclusion based on observation
controlled experiment
involves changing one factor and observing its effect on one thing while keeping all other things constant
variable
factor that can be changed in an experiment
independent variable
factor that is intentionally varied by the experimenter
dependent variable
factor that may change as a result of changes purposefully made to the independent variable
constant
variable that is not changed in an experiment
scientific method
processes scientists use to collect information and answer questions
model
any representation of an object or an event that is used as a tool for understanding the natural world; can communicate observations and ideas, test predictions, and save time, money, and lives
theories/laws
theories: explain how nature works
laws: describes what nature does under certain conditions
both: based on tested hypothesis, supported by data, and help unify a particular field
observation/inference
observation: a recored or description of an occurrence or pattern in nature
inference: a drawn conclusion based on observations
density
mass of an object divided by its volume
D = M/V
earthquake
sudden release of energy within Earth's crust that causes wave movement in the rock layers of the crust
lithosphere
rigid layer of Earth about 100km thick, made of the crust and a part of the upper mantle
inner core
solid, innermost layer of Earth's interior that is the hottest part of Earth and experiences the greatest amount of pressure
outer core
layer of Earth that lies above the inner core and is thought to be composed mostly of molten metal
plate
section of Earth's crust and rigid, upper mantle that moves slowly around the asthenosphere
mantle
largest layer of Earth's interior that lies above the outer core and is solid, yet flows slowly
crust
Earth's outermost layer that is the thinnest under the oceans and thickest through the mountains and contains all features of Earth's surface
subduction
a type of plate movement that occurs when one plate sinks beneath another plate
fault
large fracture in rock along which movement occurs
erosion
removal process by which products of weathering are moved to other locations
fault-block mountain
sharp, jagged mountains made of huge, tilted blocks of rock that are separated from surrounding rock by faults and form because of pulling forces
folded mountain
mountain that forms by the folding of rock layers caused by compressive forces
unwarped mountain
mountain that forms when forces inside Earth push up on the crust
volcano
an opening in Earth's surface that erupts sulfurous gases, ash, and lava; generally a mountain-like structure
isostasy
principle stating that Earth's lithosphere floats on a plastic-like upper part of the mantle called the asthenosphere
Earth's interior
four specific layers:
inner core: innermost layer, made of solid iron, pressured, hottest part of Earth
outer core: lies above inner core, made of molten metal, slows down seismic waves, liquid iron
mantle: largest layer, thickest layer, solid, but flows
crust: outermost layer, thinnest, contains Earth's features
plate movement
all are theories;
convection, density differences (uneven heating), ridge push (causes ocean plates to slide), slab pull (plates sink when colliding)
plates are convergent (move together), divergent (move apart), and slide past each other
mountains and shaping forces
fault block: made of huge, tilted blocks of rock that are separated from surrounding rock by faults; tension forces (pull)
folded: formed by the folding of rock layers; compression forces (push)
unwarped: formed when forces inside Earth push up on the crust; compression forces (push)
volcanic: form when lama and ash build up in one area over time; tension forces (pull..?)
acid rain
acidic moisture, with a pH below 5.6
weathering
natural mechanical or chemical process that causes rock to change by breaking them down and causing them to crumble
mechanical weathering
process that breaks rocks down into smaller pieces without changing them chemically
soil
mixture of weathered rock, organic matter, water, and air that evolves over time and supports the growth of plant life
topography
configuration of surface features, including shape, position, and slope; also influences the type and composition of soils that develop
chemical weathering
process in which the chemical composition of rocks is changed by agents such as natural acids and oxygen
mass movement
occurs when gravity alone causes rock or sediment to move down a slope
cirque
a large bowl formed by valley glaciers by removing rock from mountaintops
glacier
formed in cold regions; two types: continental and valley
loess
accumulation of silt when it is deposited
runoff
water that flows over Earth's surface
sheet flow
water flowing downhill as a thin sheet
mechanical and chemical processes
mechanical--ice wedging: frozen water in cracks expands, temperature rises, and causes ice to thaw (cycle that breaks up rocks)
gravity: pulls large rocks down to break
plants and animals: plants grow in cracks where water collects and roots expand, animals burrow through rock, loosen soil, and break rock apart
wind: takes sediments away, breaking them down
chemical--natural acids: "everyday" elements combine to form acids, cause reactions or formations, and thus change chemical composition
plant acids: tannin/produced by plants, dissolve rock minerals, weaken rock
sulfuric acid: mixes with water to form acids
water: mixes with elements to form acids
oxygen: oxidation causes minerals containing iron to weather due to oxygen and weakens rock
factors of soil formation
parent rock: breaks down and forms smaller rocks after weathering
slope of land: with topography, influences soil development
climate: affects amount of organic material in soil
time: needed for rocks to weather and soil to form
organisms: lichens take nutrients starting to break down, roots break down parent rock
agents of erosion
gravity: force that pulls every object toward every other object
ice: causes glaciers, buries mountain ranges
wind: lifts and carries sediments
water: runoff, faster means more material
element
a substance that cannot be broken down into simpler substances
period
horizontal row of elements in the periodic table whose properties change gradually and predictably
group
family of elements in the periodic table that have similar physical or chemical properties
metal
element that has luster, is malleable, ductile, and a good conductor of hear and electricity
nonmetal
element that is usually a gas or brittle solid at room temperature and is a poor conductor of heat and electricity
metalloid
element that shares some properties with both metals and nonmetals
transition elements
elements in group 3-12 in the periodic table, all of which are metals
representative elements
elements in groups 1 and 2 and 13-18 in the periodic table table that include metals, nonmetals, and metalloids
atomic number
the number of protons in the nucleus of a given element
alkali metals
elements in group 1 of the periodic table; likes to combine with the halogens
halogens
elements in group 17 of the periodic table; likes to combine with the alkali metals
alkaline earth metals
elements in group 2 of the periodic table
noble gases
elements in group 18 of the periodic table
semiconductor
element that does not conduct electricity as well as a metal but conducts it better than a nonmetal
mass number
the sum of neutrons and protons in the nucleus of an atom
catalyst
substance that can make something happen faster but not change itself
lanthanides
the first series of inner transition elements which goes from cerium to lutetium
actinides
the second series of inner transition elements which goes from thorium to lawrencium
element key
has element, the atomic number, the symbol, the atomic mass, and the state of matter
the atomic number is the number of protons in the element
the symbol is (usually) a short abbreviation of the element, one to two letters
the atomic mass is the sum of neutrons and protons in the nucleus of an atom
the logo for the state of matter shows if the element is a solid, liquid, or gas at room temperature
gases are marked with a balloon
whereas solids are marked with a cube
liquids are marked with a water droplet
unnatural elements are marked with a bulls-eye
organization of periodic table
divided into groups and periods
groups: contain elements that have similar physical or chemical properties
periods: rows of elements in the periodic table whose chemical and physical properties change gradually and predictably
the representative elements are groups 1-2 and 13-18; they include metals, metalloids, and nonmetals
groups 3-12 are transition elements; all are metals
the inner transition elements are placed below the main table and are called the lanthanide and actinide series
properties of representative elements
check out "chart template 4.2".. I can't copy and paste the chart
chemical change
change in which the identity of a substance changes and forms a new substance or substances
electron cloud
area where negatively charged electrons, arranged in energy levels, travel around an atom's nucleus
energy level
the different areas for an electron in an atom
electron dot diagram
chemical symbol for an element, surrounded by as many dots as there are electrons in its outer energy level
chemical bond
force that holds two atoms together
compound
pure substance that contains two or more elements
ion
atom that is no longer neutral because it has gained or lost an electron
ionic bond
attraction that holds oppositely charged ions close together
metallic bond
bond formed when metal atoms share their pooled electrons
covalent bond
chemical bond formed when atoms share electrons
molecule
neutral particle formed when atoms share electrons
polar bond
bond resulting from the unequal sharing of electrons
chemical formula
combination of symbols and numbers that indicates which elements and how mant atoms of each element are present in a molecule
electron arrangement in an atom
are present in energy levels around the nucleus
electron arrangement's effect on atom placement
arrangement of electrons is pretty much responsible for many physical and chemical properties of the element
ionic/covalent compounds
ionic compounds: takes oppositely charged bonds close together; either gains or loses an electron
covalent compounds: bond that forms between nonmetal atoms when they share electrons
both: form compounds after bonding
compounds/molecules
compounds: pure substances that contain two or more elements
molecules: neutral particles formed when atoms share electrons
atom
a small particle that makes up most types of matter
matter
anything that takes up space and has mass
solid
matter with definite shape and volume; has tightly packed particles that move mainly by vibrating
liquid
matter with a definite volume but no definite shape that can flow from one place to another
viscosity
a liquid's resistance to flow
gas
matter that does not have a definite shape or volume; has particles that move at high speeds in all directions
surface tension
the uneven forces acting on the particles on the surface of a liquid
energy
the ability to do work or cause change
thermal energy
the sum of the kinetic and potential energy of the particles in a material
temperature
a measure of the average value of the kinetic energy of the particles in a material
heat
movement of thermal energy from a substance at a higher temperature to a substance at lower temperature
melting
change of matter from a solid state to a liquid state
freezing
change of matter from a liquid state to a solid state
vaporization
change of matter from a liquid state to a gas
condensation
change of matter from a gas to a liquid state
force
a push or pull
pressure
force exerted on a surface divided by the total area over which the force is exerted
P = F/A
buoyant force
upward force exerted on an object immersed in a fluid
Pascal's principle
states that when a force is applied to a confined fluid, an increase in pressure is transmitted equally to all parts of the fluid
Archimedes' principle
states that the buoyant force on an object is equal to the weight of the fluid displaced by the object
states of matter and arrangement of particles
solid: matter with definite shape and volume; their particles vibrate in place and keep their shape and volume maintained.. because a solid has a specific shape, the particles make sure that that the shape and volume is the same
liquid: matter that has a definite volume but no definite shape; the particles stay close together, but are free to move past one another... because a liquid has a definite volume, it must have the same weight; whereas because it has no specific shape, the particles can move around a little bit
gas: matter that doesn't have a definite shape or volume; the particles in a gas move at high speeds in all directions... because a gas has no definite volume or shape, the particles are free to do pretty much whatever they want
thermal energy/temperature
thermal energy: the sum of the kinetic and potential energy of the particles in a material
temperature: a measure of the average value of the kinetic energy of the particles in a material
comparison: both use kinetic energy
changes of thermal energy/changes of state
thermal energy: depends on the amount of the substance and the kinetic energy of particles in the substance; during changes of state, the temperature of the substance stays the same
changes of state: vaporization is change from the liquid to gaseous state; condensation is the change from gaseous state to the liquid state; sublimation is the process of a substance going from the solid to gas state without ever being in the liquid state
both: depend on the amount of the substance
floating/sinking
water pressure increases with depth; the pressure pushing up on the bottom of the object is greater than the pressure pushing down on it because the bottom of the object is greater than on the top; if the buoyant force is equal to the weight of an object, the object will float; if the buoyant force is less than the weight of an object, the object will sink
pressure transmission through fluids
when a force is applied to a confined fluid, an increase in pressure is transmitted equally to all parts of the fluid
a good example of Pascal's principle is hydraulic systems using this principle to increase force; the force applied to the piston (left) increases the pressure within the fluid; that increase in pressure is transmitted to the piston (right); if both pistons have the same area, the force on one piston will be equal to the other; but, if the one on the right has a greater surface area, the resulting force will be greater. The same pressure multiplied by a larger area equals greater force
the formula for pressure is: pressure = force/area (P = F/A)
the formula for force is: force = pressure x area (F = P x A)