Science terms meaning and definition study guide

 

 

Science terms meaning and definition study guide

 

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Science terms meaning and definition study guide

Section 1

  1. Controlled experiment:  an experiment in which only one variable is manipulated at a time
  2. Data: facts, figures, and other evidence gathered through observations
  3. Hypothesis:  a possible explanation for a set of observations or answer to a scientific question; must be testable
  4. Inferring: the process of making an inference, an interpretation based on observation and prior knowledge
  5. Manipulated variable the one factor that a scientist changes during an experiment; also called independent variable
  6. Observing:  the process of using one or more of your senses to gather information
  7. Predicting:  the process of forecasting what will happen in the future based on past experience or evidence
  8. Responding variable: the factor that changes as a result of changes to the manipulated, or independent, variable in an experiment; also called dependent variable.
  9. Science:  a way of learning about the natural world through observations and logical reasoning; leads to a body of knowledge
  10. Scientific inquiry: the ongoing process of discovery in science; the diverse ways in which scientists study the natural world and propose explanations based on evidence they gather.
  11. Scientific law: a statement that describes what scientists expect to happen every time under a particular set of conditions
  12. Scientific theory: a well-tested concept that explains a wide range of observations
  13. Variable:  a factor that can change in an experiment

Section 2

  1. Astronomer:  a scientist who studies the universe beyond Earth
  2. Constructive force:  a force that builds up mountains and landmasses on Earth’s surface
  3. Destructive force a force that slowly wears away mountains and other features on the surface of Earth
  4. Earth science: the science that focuses on planet Earth and its place in the universe
  5. Energy:  the ability to do work or cause change
  6. Environmental scientist:  a scientist who studies the effects of human activities on Earth’s land, air, water and living things and also tries to solve problems relating to the use of resources
  7. Geologist:  a scientist who studies the forces that make and shape planet Earth
  8. Meteorologist: a scientist who studies the causes of weather and tries to predict it
  9. Oceanographer:  a scientist who studies Earth’s oceans
  10. System:  a group of related parts that work together.

Section 3

  1. Engineer: a person who is trained to use both technological and scientific knowledge to solve practical problems
  2. Technology:  how people modify the world around them to meet their needs or to solve practical problems.

 

Section 1

  1. anticline an upward fold in rock formed by compression of Earth’s crust
  2. compression stress that squeezes rock until it folds or breaks
  3. footwall the block of rock that forms the lower half of a fault
  4. hanging wall the block of rock that forms the upper half of a fault
  5. normal fault a type of fault where the hanging wall slides downward; caused by tension in the crust
  6. plateau  a plateau that has high elevation and a more or less level surface.
  7. reverse fault a type of fault where the hanging wall slides upward; caused by compression in the crust.
  8. shearing stress that pushes masses of rock in opposite directions, in a sideways movement
  9. stress  a stress that acts on rock to change its shape or volume
  10. strike-slip fault a type of fault where rocks on either side move past each other sideways with little up-or-down motion
  11. syncline a downward fold in rock formed by compression in Earth’s crust
  12. tension stress that stretches rock so that it becomes thinner in the middle

Section 2

  1. earthquake  the shaking that results from the movement of rock beneath Earth’s surface
  2. epicenter the point on Earth’s surface directly above an earthquake’s focus
  3. focus  the point beneath Earth’s surface where rock breaks under stress and causes an Earthquake
  4. magnitude the measurement of an earthquake’s strength based on seismic waves and movement along faults
  5. Mercalli scale a scale that rates earthquakes according to their intensity and how much damage they cause at a particular place
  6. moment magnitude scale a scale that rates earthquakes by estimating the total energy released by an earthquake
  7. P wave a type of seismic wave that compresses and expands the ground
  8. Richter scale  a scale that rates an earthquake’s magnitude based on the size of its seismic waves
  9. S wave a type of seismic wave that moves the ground
  10. seismograph a device that records ground movements caused by seismic waves as they move through Earth
  11. surface wave a type of seismic wave that forms when P waves and S waves reach Earth’s surface.

Section 3

  1. friction the force that opposes the motion of one surface as it moves across another surface
  2. seismogram the record of an earthquake’s seismic waves produced by a seismograph

Section 4

  1. aftershock an earthquake t occurs after a larger earthquake in the same area
  2. base-isolated building a building mounted on bearings designed to absorb the energy of an earthquake
  3. liquefaction the process by which an earthquake’s violent movement suddenly turns loose soil into liquid mud
  4. tsunami a giant wave usually caused by an earthquake beneath the ocean floor

 

Questions page 75.

  1. When the water inside the dropper rises the dropper starts sinking. When the water inside the dropper lowers the dropper rises.
  2.  The denser the dropper is (the more water is has in it) the lower it is in the water.
  3. A submarine can control the amount of water to control their densities to go up or down in the water.

Three familiar states of matter: solid, liquid and gas (p 78)

Section 1 Review page 81

  1. List three main points of the kinetic theory of matter.

1. Atoms and molecules are always in motion
2. Particles move faster at high temperatures than they do at low temperatures.
3. At any temperature heavier particles move slower than lighter particles do.

  1. State two examples for each of the four states of matter.

Solid: marbles and brass metal or coins
Liquids: water, orange juice, milk, mercury
Gas: oxygen, nitrogen, helium
Plasma: fire and lightening

  1. Compare the shape of and volume of solids, liquids, and gases.

Solids: have definite volume and shape
Liquids: have definite volume but no definite shape
Gases: have neither definite volume nor definite shape

  1. Describe the relationship between temperature and kinetic energy.

Temperature is a direct measure of average kinetic energy.

  1. Compare the temperature and thermal energy of hot soup in a small mug and that of hot soup in a large bowl.

Both would have the same temperature, but the large bowl of soup has more thermal energy than the small mug because there is more matter present in the bowl.

  1. Which particles have the strongest attraction between them: the particles of a gas, the particles of a liquid, or the particles of a solid?

Particles of a solid have a stronger attraction to one another

  1. Use the kinetic theory to explain how a dog could find you by your scent.

The gas particles move freely in all directions. Therefore a dog could get your scent if you touch something or walked on the ground, it could pick up your scent.

Section 2 Review page 88

  1. Describe the following changes of state, and explain how particles behave in each state.
    1. Freezing: it goes from a liquid to a solid and the particles slow down
    2. Boiling: it goes from a liquid to a gas and the particles speed up
    3. Sublimation: it goes from a solid to a gas and the particles speed up
    4. Melting: it goes from a solid to a liquid and the particles speed up
  2. State whether energy is released or whether energy is required for the following changes of state to take place
    1. Melting: energy is required
    2. Evaporation: energy is required
    3. Sublimation: energy is required
    4. Condensation: energy is being released
  3. Describe the role of energy when ice melts and when water vapor condenses to form liquid water.

As energy is transferred to ice, the attraction between water molecules is broken and the ice melts. As water vapor releases energy, the attraction between molecules increases and liquid water condenses.

  1. State the law of conservation of mass and the law of conservation of energy, and explain how they apply to changes of state.

Law of conservation of mass: Mass can not be created or destroyed
Law of conservation of energy: Energy can not be created or destroyed
During a change of state the total mass and total energy remain constant.

  1. If you used dry ice in your holiday punch, would it become watery after an hour? Why or why not?

No, because dry ice is solid carbon dioxide. It undergoes sublimation and therefore turns directly from a solid into a gas.

Section 3 Review page 94

  1. Explain how differences in fluid pressure create buoyant force on an object.

Fluid pressure is exerted on all sides of an object. The horizontal pressures cancel each other out. The pressure exerted at the bottom is greater than the pressure exerted at the top, and it creates a buoyant forces known as lift (buoyancy).

  1. State Archimedes’ principle, and give an example of how you could determine a buoyant force.

Archimedes’ principle states that the buoyant force in a fluid equals the weight of the fluid the object displaces. We could weigh the fluid that was displaced.

  1. State Pascal’s principle. Give an example of its use.

Pascal’s principle states that pressure applied to a fluid in a closed container is transmitted equally throughout the fluid. Hydraulic lifts and hydraulic jacks would be two examples.

  1. Compare the viscosity of milk and the viscosity of molasses.

The viscosity of molasses is greater than that of milk

  1. An object weighs 20 N. It displaces a volume of water that weighs 15 N.
    1. What is the buoyant force on the object? The buoyant force will be 15 N
    2. Will the object float or sink? Explain. It will sink because its weight exceeds its buoyant force.
  2. Iron has a density of 7.9 g/cm3. Mercury has a density of 13.6 g/cm3. Will iron float or sink in mercury. Explain. It will float because its density is less than that of mercury.
  3. Two boats in a flowing river are sailing side-by-side with only a narrow space between them.
    1. What happens to the fluid speed and the pressure between the two boats? The fluid speed increases because the fluid pressure decreases.
    2. How could the changes in fluid speed and pressure lead to a collision of the boats? As the fluid speed between the boats increases the fluid pressure decreases, so if this happens the boats would be pushed together.
  4. A water bed that has an area of 3.75 m2 weighs 1,025 N. Find the pressure that the water bed exerts on the floor.

1,025 N divide by 3.75 m2 equals 273 Pascals

  1. The small piston of a hydraulic lift has an area of 0.020 m2. A car weighing 12,000 N is mounted on the large piston (area = 0.90 m2). What force must be applied to the small piston to support the car?

12,000 N divide by 0.90 m2 times 0.020 m2 equals 270 N

Section 4 Review page 101

  1. List four properties of gas.

Gases will flow, they have low densities, they are compressible, and they expand to fill their containers.

  1. Explain why the volume of a gas can change.

The attraction between gas particles is not very strong so the volume of a gas can easily change.

  1. Describe how gases are different from solids and liquids, and give examples.

Unlike solids and liquids gases have very low densities and can easily change volume.
An example: filling tires, filling balloons, filling scuba tanks

  1. Identify what causes the pressure exerted by gas molecules on their container.

By the gas particles colliding with the walls of their container.

  1. Restate Boyle’s law, Charles’s law, and Gay-Lussac’s law in your own words.
    1. Boyle’s Law: the volume of a gas increases as pressure decreases (at a constant temperature)
    2. Charles’s Law: the volume of gas increases as the temperature increases
    3. Gay-Lussac’s Law: gas pressure increases as temperature increases at a constant volume.
  2. Identify a real-life example for each of the three gas laws.
    1. Boyle’s Law: let the air out of a tire, the air expands outside of the tire, as the pressure on the air decreases
    2. Charles’s Law: when a balloon is exposed to heat it will expand.
    3. Gay-Lussac’s Law: if you heat a spray can it may explode due to an increase in pressure.
  3. Why do gases have low densities?

Their particles are very far apart.

  1. When scientists record the volume of a gas, why do they also record the temperature and the pressure?

The volume of a gas can be changed by changing either the temperature or the pressure.

  1. Predict what would happen to the volume of a balloon left on a sunny window-sill. Which gas law predicts this result?

It would cause the temperature on the inside of the balloon to increase. Charles’s law, the volume will increase as the temperature increases.

  1. A partially inflated weather balloon has a volume of 1.56 x 103 L and pressure of 98.9 kPa. What is the volume of the balloon when the balloon is released to a height where the pressure is 44.1 kPa?

Take (1.56 x 103 L) times 98.0 kPa over 44.1 kPa. Equals 3.50 x 103 L


END OF CHAPTER QUESTIONS page 106-107

  1. Make a comparison table to compare the five changes of state that are described in this chapter.

Melting
Freezing
Evaporation
Condensation
Sublimation

  1. Describe four states of matter by using the terms solid, liquid, gas, and plasma. Describe the behavior of particles in each state.

Solid: the particles are held closely together and they vibrate
Liquid: the particles are close together but they slide past one another
Gas: the particles are spread apart and they fill the available space
Plasma: the particles spread apart to fill spaces and they are broken apart

  1. Describe how pressure is exerted by fluids.

Fluids exert pressure evenly in all directions.

  1. Describe the buoyant force, and explain how it relates to Archimedes’ principle.

Buoyant force is the upward force exerted on an object floating on a fluid. Archimedes’ principle states that the buoyant force is equal to the weight of the volume of the fluid that is displaced by the object.

  1. Which of the following assumptions is not part of the kinetic theory?
  2. Three common states of matter are
  3. During which of the following changes of state do atoms or molecules become more ordered?   B. condensation
  4. Which of the following describes what happens as the temperature of a gas in a balloon increases?
  5. Fluid pressure is always directed
  6. Matter that flows to fit its container includes
  7. If an object that weighs 50 N displaces a volume of water that weighs 10 N, what is the buoyant force on the object?
  8. State the law of conservation of energy and the law of conservation of mass. Explain what happens to energy and mass in a change of state.
  9. For each pair, explain the difference in meaning
    1. solid and liquid: A solid has definite shape and volume. A liquid the substance takes the shape of its container, but has definite volume.
    2. Boyle’s law and Charles’s law: Boyle’s law states that when the pressure of a gas increases its volume decreases. Charles’s law states that when the temperature of a gas increases its volume also increases.
    3. Gay-Lussac’s law and Pascal’s principle: Gay-Lussac’s law states that when the temperature of a gas increases its pressure also increases. Pascal’s principle states that when the pressure is applied to a fluid in a closed container it is transmitted equally throughout the fluid.
  10. Using the graph: What type of relationship does the graph represent: direct or inverse?
  11. To which law or principle does the graph apply?
  12. Explain what happens to the pressure of a gas if the volume of the gas is tripled. Assume that the temperature remains constant.

Boyle’s law states that the volume of a gas in inversely proportional to its pressure. So if the volume is tripled the pressure would drop to 1/3.

  1. Why are liquids instead of gases used in hydraulic brakes?

Liquids are used instead of gases because they can not be compressed easily. Gases are easily compressed.

 

Section 1

  1. hot spot: an area where magma from deep within the mantle melts through the crust above it.
  2. island arc:  a string of islands formed by the volcanoes along a deep-ocean trench.
  3. lava: liquid magma that reaches the surface; also the rock formed when liquid lava hardens
  4. magma: the molten mixture of rock-forming substances, gases, and water from the mantle
  5. Ring of Fire: a major belt of volcanoes that rims the Pacific Ocean
  6. volcano: a weak spot in the crust where magma has come to the surface

Section 2

  1. aa: a slow-moving type of lava that hardens to form rough chunks; cooler than pahoehoe
  2. chemical property: any property of a substance that produces a change in the composition of matter
  3. compound:  a substance in which two or more elements are chemically joined
  4. element:  a substance in which all the atoms are the same that cannot be broken down into other substances
  5. pahoehoe:  a hot, fast-moving type of lava that hardens to form smooth, ropelike coils
  6. physical property:  any characteristic of a substance that can be observed or measured without changing the composition of the substance
  7. silica:  a material found in magma that is formed from the elements oxygen and silicon
  8. viscosity:  a liquid’s resistance to flowing

Section 3

  1. crater:  a bowl-shaped area that forms around a volcano’s central opening; a large round pit caused by the impact of a meteroid
  2. dormant: a volcano that is not currently active, but that may become active in the future
  3. extinct: a volcano that is no longer active and is unlikely to erupt again
  4. lava flow: liquid magma that reaches the surface; also the rock formed when liquid lava hardens
  5. magma chamber:  the pocket beneath a volcano where magma collects
  6. pipe: a long tube through which magma moves from the magma chamber to Earth’s surface
  7. pyroclastic flow:  the expulsion of ash, cinders, bombs, and gases during an explosive volcanic eruption
  8. vent:  the opening through which molten rock and gas leave a volcano

Section 4

  1. batholith: a mass of rock formed when a large body of magma cools inside the crust
  2. caldera: the large hole at the top of a volcano formed when the roof of a volcano’s magma chamber collapses
  3. cinder cone: a steep, cone-shaped hill or small mountain made of volcanic ash, cinders, and bombs piled up around a volcano’s opening
  4. composite volcano: a tall, cone-shaped mountain in which layers of lava alternate with layers of ash and other volcanic materials
  5. dike: a slab of volcanic rock formed when magma forces itself across rock layers
  6. geothermal activity: the heating of underground water by magma
  7. geyser a fountain of water and steam that builds up pressure underground and erupts at regular intervals
  8. shield volcano: a wide, gently sloping mountain made of layers of lava and formed by quiet eruptions
  9. sill: a slab of volcanic rock formed when magma squeezes between layers of rock
  10. volcanic neck: a deposit of hardened magma in a volcano’s pipe

 

Section 1

  1. groundwater: water that fills the cracks and spaces in underground soil and rock layers
  2. precipitation: any form of water that falls from clouds and reaches Earth’s surface
  3. water cycle:  the continual movement of water among Earth’s atmosphere, oceans, and land surface through evaporation, condensation, and precipitation.

Section 2

  1. divide: a ridge of land that separates one watershed from another.
  2. habitat:  the place where an organism lives and where it obtains all the things it needs to survive
  3. reservoir:  a lake that stores water for human use
  4. tributary: a stream or smaller river that feeds into a main river
  5. watershed: the land area that supplies water to a river system
  6. wetland:  a land area that is covered with a shallow layer of water during some or all of the year

Section 3

  1. aquifer: an underground layer of rock or sediment that holds water
  2. artesian well: a well in which water rises because of pressure within the aquifer
  3. geyser: a fountain of water and steam that builds up pressure underground and erupts at regular intervals
  4. impermeable: a characteristic of materials, such as clay and granite, through which water does not easily pass
  5. permeable: characteristic of material that is full of tiny, connected air spaces that water can seep through
  6. saturated zone: a layer of permeable rock or soil in which the cracks and pores are totally filled with water
  7. spring:  a place where groundwater flows to the surface
  8. unsaturated zone:  a layer of rocks and soil above the water table in which the pores contain air as well as water
  9. water table: the top of the saturated zone, or depth to the groundwater under Earth’s surface

Section 4

  1. conservation: the practice of using less of a resource so that it will not be used up
  2. irrigation: the process of supplying water to areas of land to make them suitable for growing crops
  3. nonpoint source:  a widely spread source of pollution that is difficult to link to a specific point of origin
  4. point source: a specific source of pollution that can be identified
  5. pollutant: a harmful substance in the air, water, or soil
  6. water pollution:  the addition of any substance that has a negative effect on water or the living things that depend on the water

Section 5

  1. coagulation: the process by which particles in a liquid clump together
  2. coliform: a type of bacteria found in human and animal wastes
  3. concentration:  the amount of one substance in a certain volume of another substance
  4. filtration:  the process of passing water through a series of screens that allow the water through, but not larger solid particles
  5. hardness:  the level of the minerals calcium and magnesium in water
  6. pH: the measurement of how acidic or basic a substance is, on a scale of 0 (very acidic) to 14 (very basic
  7. water quality: the degree of purity of water, determined by measuring the substances in water besides water molecules

Section 1
carbon film: a type of fossil consisting of an extremely thin coating of carbon on rock
cast: a fossil that is a copy of an organism’s shape, formed when minerals seep into a mold
evolution: the process by which all the different kinds of living things have changed over time
extinct:  describes a type of organism that no longer exists anywhere on Earth
fossil: a trace of an ancient organism that has been preserved in rock
mold: a fossil formed when an organism buried in sediment dissolves, leaving a hollow area.
paleontologist:  a scientist who studies fossils to learn about organisms that lived long ago.
petrified fossil:  a fossil in which minerals replace all or part of an organism
scientific theory: a well-tested concept that explains a wide range of observations
sedimentary rock: a type of rock that forms when particles from other rocks or the remains of plants and animals are pressed and cemented together
trace fossil:  a type of fossils that provides evidence of the activities of ancient organisms

Section 2
absolute age: the age of rock given as the number of years since the rock formed
extrusion: an igneous rock layer formed when lava flows onto Earth’s surface and hardens
fault:  a break or crack in Earth’s lithosphere along which the rocks move.
index fossil:  fossils of widely distributed organisms that lived during only one short period
intrusion: an igneous rock layer formed when magma hardens beneath Earth’s surface
law of superposition:  the geologic principle that states that in horizontal layers of sedimentary rock, each layer is older than they layer above it and younger than the layer below it
relative age: the age of rock compared to the ages of rock layers
unconformity:  a place where an old, eroded rock surface is in contact with a newer rock layer

Section 3
atom: the smallest particle of an element
element: a substance in which all the atoms are the same and cannot be broken down into other substances
half-life: the time it takes for half of the atoms of a radioactive element to decay
radioactive decay: the breakdown of a radioactive element, releasing particles and energy

Section 4
era: one of the three long units of geological time between the Precambrian and the present
geologic time scale: a record of the geologic events and life forms in Earth’s history
period: one of the units of geologic time into which geologists divide eras

Section 5
comet: a loose collection of ice, dust and small rocky particles, typically with a long, narrow orbit of the sun
continental drift: the hypothesis that the continents slowly move across the Earth’s surface

Section 6
amphibian: a vertebrate that lives part of its life on land and part of its life in water
invertebrate:  an animal without a backbone
mammal:  a warm-blooded vertebrate that feed its young milk
mass extinction: when many types of living things become extinct at the same time
reptile:  a vertebrate with scaly skin that lays eggs with tough, leathery shells
vertebrate:  an animal with a backbone

 

Section 1

  1. frequency: the number of waves that pass a specific point in a given amount of time
  2. groin:  a wall made of rocks or concrete that is built outward from a beach to reduce erosion
  3. longshore drift: the movement of water and sediment down a beach caused by waves coming in to shore at an angle
  4. rip current: a rush of water that flow rapidly back to sea through a narrow opening in a sandbar.
  5. tsunami: a giant wave usually caused by an earthquake beneath the ocean floor
  6. wave: the movement of energy through a body of water
  7. wave height: the vertical distance from the crest of a wave to the trough
  8. wavelength: the horizontal distance between the crest of one wave and the crest of the next wave

Section 2

  1. neap tide: a tide with the least difference between low and high tide that occurs when the sun and moon pull at right angles to each other at the first and third quarters of the moon
  2. spring tide: a tide with the greatest difference between high and low tide that occurs when the sun and the moon are aligned with Earth at the new moon and the full moon
  3. tides: the daily rise and fall of Earth’s waters on its coastlines

Section 3

  1. salinity: the total amount of dissolved salts in a water sample
  2. submersible: an underwater vehicle built of strong materials to resist pressure

Section 4

  1. climate: the average, year-after-year conditions of temperature, precipitation, winds, and clouds in an area
  2. Coriolis effect: the effect of Earth’s rotation on the direction of winds and currents
  3. current:  a large stream of moving water that flows through the oceans
  4. El Nino:  A climate event that occurs every two to seven years in the Pacific Ocean, during which winds shift and push warm water toward the coast of South America
  5. upwelling:  the movement of cold water upward from the deep ocean that is caused by wind.

 

Section 1

  • Elevation: height above sea level
  • Landform region: a large area of land where the topography is similar
  • Landforms: a feature of topography formed by the processes that shape Earth’s surface
  • Mountain: a landform with high elevation and high relief
  • Mountain range: a series of mountains that have the same general shape and structure
  • Plain: a landform made up of flat or gently rolling land with low relief
  • Plateau: a landform that has high elevation and a more or less level surface
  • Relief: the difference in elevation between the highest and lowest parts of an area
  • Topography: the shape of land determined by elevation, relief and landforms.

Section 2

  • Degree: a unit to measure distance around a circle. One degree equals 1/360 of a full circle
  • Equator: an imaginary line that circles Earth halfway between the North and South Poles
  • Globe: a sphere that represents Earth’s entire surface
  • Hemisphere: One half of the sphere that makes up Earth’s surface
  • Key: a list of symbols used on a map
  • Latitude: the distance in degrees north or south of the equator
  • Longitude: the distance in degrees east or west of the prime meridian
  • Map: a flat model of all or part of Earth’s surface as seen from above
  • Map projections:  a framework of lines that helps to show landmasses on a flat surface
  • Prime meridian: the line that makes a half circle from the North Pole to the South Pole and that passes through Greenwich, England
  • Scale:  used to compare distance on a map or globe to distance on Earth’s surface
  • Symbol:  On a map, pictures used by mapmakers to stand for features on Earth’s surface

Section 3

  • Digitizing: converting information to numbers for use by a computer
  • Global Positioning System: a method of finding latitude and longitude using a network of satellites
  • Pixel: the tiny dots in a satellite image
  • Satellite image:  pictures of the land surface based on computer data collected from satellites
  • Surveying:  the process of gathering data for a map by using instruments and the principles of geometry to determine distance and elevations

Section 4

  • Contour interval: the difference in elevation from one contour line to the next
  • Contour Line: a line on a topographic map that connects points of equal elevation
  • Index contour: on a topographic map, a heavier contour line that is labeled with elevation of that contour line in round units.
  • Topographic map:  a map that shows the surface features of an area

Section 1

  1. matter (p. 45): anything that has mass and takes up space
  2. element (p. 46): a substance that cannot be broken down into simpler substances by chemical means
  3. atom (p. 46): the smallest unit of an element that keeps the element’s chemical properties
  4. molecule (p. 47): the smallest unit of a substance that behaves like the substance
  5. compound (p. 47): a substance made up of atoms of different elements
  6. pure substance (48): a matter that has a fixed composition and definite properties
  7. mixture (48): a combination of substances that are not chemically combined

Section 2

  1. melting point (p. 52): the temperature at which a substance changes from a solid to a liquid
  2. boiling point (p. 52): the characteristic at which a liquid changes to a gas
  3. density (p. 54): a measurement of how much matter is contained in a certain volume of a substance.
  4. reactivity (p. 56): the capacity of a substance to combine with another substance

Section 3

  1. physical change (p. 59): A change that affects one or more physical properties of a substance without changing the identity of the substance.
  2. chemical change (p. 61): A change that happens when one or more substances are changed into entirely new substances that have different properties.

 

Section 1

  1. athenosphere: the soft layer of the mantle on which the lithosphere floats
  2. basalt: a dark, dense, igneous rock with fine texture, found in oceanic crust
  3. crust: the layer of rock that forms Earth’s outer surface
  4. granite: a usually light-colored igneous rock that is found in continental crust
  5. lithosphere: a rigid layer made up of the uppermost part of the mantle and the crust
  6. mantle: the layer of hot, solid material between Earth’s crust and core
  7. outer core: a layer of molten iron and nickel that surrounds the inner core of Earth.
  8. pressure: the force exerted on a surface divided by the total area over which the force is exerted
  9. seismic waves: vibrations that travel through Earth carrying the energy released during an earthquake.

Section 2

  1. conduction: the direct transfer of thermal energy from one substance to another substance that it is touching.
  2. convection current: the movement of a fluid, caused by differences in temperature, that transfers heat from one part of the fluid to another
  3. convection: the transfer of thermal energy by the movement of a fluid
  4. density: the amount of mass of a substance in a given volume; mass per unit volume
  5. radiation: the direct transfer of energy through space by electromagnetic waves

Section 3

  1. continental drift: the hypothesis that the continents slowly move across Earth’s surface
  2. fossil: a trace of an ancient organism that has been preserved in rock
  3. Pangaea: the name of the single landmass that broke apart 200 million years ago and gave rise to today’s continents

Section 4

  1. deep-ocean trench: a deep valley along the ocean floor beneath which oceanic crust slowly sinks toward the mantle
  2. mid-ocean ridge: an undersea mountain chain where new ocean floor is produced
  3. sea-floor spreading:  the process by which molten material adds new oceanic crust to the ocean floor
  4. sonar: a device that determines the distance of an object under water by recording echoes of sound waves
  5. subduction: the process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary

Section 5

  1. convergent boundary: a plate boundary where two plates move toward each other
  2. divergent boundary:  a plate boundary where two plates move away from each other
  3. fault: a break or crack in Earth’s lithosphere along which the rocks move
  4. plate tectonics: the theory that pieces of Earth’s lithosphere are in constant motion, driven by convection currents in the mantle
  5. plate: a section of the lithosphere that slowly moves over the asthenosphere, carrying pieces  of continental and oceanic crust
  6. rift valley: a deep valley that forms where two plates move apart
  7. scientific theory: a well-tested concept that explains a wide range of observations
  8. transform boundary: a plate boundary where two plates move past each other in opposite directions

 

Explanation of scientific terms and definitions

Branches of Science

  1. Social Science                      human behavior
  2. Natural Science         how the universe behaves
  3. Biology                     living things
  4. Zoology                    animals
  5. Botany                                plants
  6. Ecology                    balance in nature
  7. Physical Science       matter and energy
  8. Chemistry                 matter and its changes
  9. Physics                     forces and energy
  10. Geology                    Earth, physical nature and history
  11. Meteorology             atmosphere and weather
  12. Biochemistry                       matter of living things
  13. Geophysics               forces that affect the Earth

Science: the knowledge obtained by observing natural events that can be verified or tested.

Law: describes a process in nature that can be tested by repeated experiments.
Theory: an explanation of why a process takes places that is supported by a large body of evidence acquired through scientific investigation.

 

  1. Describe Democritus’s atomic theory.

Everything in the universe is made up of atoms.

  1. Summarize the main ideas of Dalton’s theory.
    1. Elements are made up of tiny unique particles called atoms.
    2. Atoms cannot be divided.
    3. Atoms of the same element are identical.
    4. Atoms of different elements can join to form molecules.
  2. Explain why Dalton’s theory was more successful tan Democritus’s theory. Dalton had experimental evidence to support his theory, while Democritus did not.
  3. Compare Thomson’s atomic model with Rutherford’s atomic model.

Thomson’s model- electrons were embedded in a sphere of positive charge
Rutherford’s model- positive charge is concentrated in the nucleus and electrons surrounded the nucleus.

  1. Analyzing elements
    1. How did the cathode-ray tube experiment lead to the conclusion that atoms contain electrons? The air was removed from the tube and the beam of negative particles was observed. This suggests that atoms are made up of smaller units with negative charges.
    2. How did the gold-foil experiment lead to the conclusion that the atom has a nucleus? the positive particles were deflected at large angles and therefore this suggests that a positive charge is concentrated in the center of the atom.  (nucleus)
  2. Making Inferences: Does the term indivisible still describe the atom? Explain. No, the atom is not indivisible. It is made up of smaller parts such as the electron.
  1. List the charge, mass, and location of each of the three subatomic particles found in atoms. The proton is positive, the neutron is neutral and electrons are negative. Protons and neutrons are found in the nucleus of an atom. The mass of a proton 1850 times greater than that of an electron.
  2. Explain how you can use an atom’s mass number and atomic number to determine the number of protons, electrons, and neutrons to determine the number of protons, electrons, and neutrons in the atom. The atomic number equals the number of protons. The number of electrons equals the number of protons. To find the number of neutrons subtract the atomic number from the mass number.
  3. Identify the subatomic particle used to define an element, and explain why this particle is used. The proton defines the element’s number because the each element always has the same number of protons, while the number of neutrons and electrons can vary.
  4. Explain why the masses of atoms of the same element may differ. Because they can have different number of neutrons. For example Hydrogen (H) H, H1Deterium, H2 Tritium. These are called isotopes.

 

  1. Calculate the number of neutrons that each of the following isotopes contains.
  2. Identify the unit that is used for atomic masses.
  3. Define Avogadro’s number, and describe how it relates to a mole of a substance.
  4. Determine the molar mass of each of the following elements
    1. Manganese, Mn
    2. Cadmium, Cd
    3. Arsenic, As
    4. Strontium, Sr
  5. If an atom loses electrons, will it have an overall charge?
  6. Predict which isotope of nitrogen is more common in nature: nitrogen-14 or nitrogen-15. (hint: What is the average atomic mass listed for nitrogen in the periodic table?)
  7. Which has a greater number of atoms 3.0 g of iron, Fe, or 2.0 g of sulfur, S?
  8. A graph of the amount of a particular element in moles versus the mass of the element in grams is a straight line. Explain why.
  9. What is the mass in grams of 0.48 mol of platinum, Pt?
  10. What is the mass in grams of 3.1 mol of mercury, Hg?
  11. How many moles does 11 g of silicon, Si, contain?
  12. How many moles does 205 g of helium, He, contain?
  1. State two key features of the modern model of the atom.
  2. Explain what determines how the energy levels in an atom are filled.
  3. Describe what happens when an electron jumps from one energy level to another.
  4. Identify how many electrons the third energy level can hold, and explain why this is the case.
  5. Compare an atom’s structure to a ladder. Identify one way in which a ladder is not a good model for the atom.
  6. Explain how Bohr’s model and the modern model of the atom differ in terms of the path of an electron.
  7. How many valence electrons does nitrogen (Z=7) have?

 

  1. Everday Words Used in Science In everday speech, the words precision and accuracy are often used interchangeably. When these terms are used in science, are their meanings the same as their everyday meanings?

Precision is the exactness of an answer while accuracy is a description of how close a measurement is to the true value of a measurement.

Using Key Terms

  1. Physical Science was once defined as “the science of the nonliving world.” Explain why that definition is no longer sufficient.

Today we tie in Physical Science with Chemistry and Biology, called Biochemistry. It is not just the nonliving world.

  1. Explain why the observation that the sun sets in the west could be called a scientific law.

Repeatedly day after day it does, so it is a law.

  1. Explain why the following statement could be considered a scientific theory: The rotation of Earth causes the sun to set.

It is a tested possible explanation of why the sun sets in the west.

  1. What is mass, and how does it differ from weight?

Mass is a quantity of matter, weight is a force that the Earth’s gravity pulls on the matter.

  1. Some features on computer chips can be as small as 35 nm. Explain why you would use scientific notation to express this quantity in meters.

It would be used because there would decrease the number of zeros.

  1. The mass of a certain elephant is 3,476 kg. A zoologist who measures the mass of that elephant finds that the mass is 3,480 kg. Is the mass measured by the zoologist accurate?

The mass is accurate because it is very close to the very actual weight of the elephant.

Understanding Key Ideas

  1. Which branch of science is not included in physical science?

D. zoology

  1. Which science deals most with energy and forces?

B. physics

  1. Using superconductors to build computers is an example of

A. technology

  1. A balance is a scientific tool used to measure

D. mass

  1. Which unit is an SI base unit?

C. kilogram

  1. The composition of the mixture of gases that makes up our air is best represented on what kind of graph?

A. pie graph

  1. In a controlled experiment

C. you change one variable throughout the experiment, and the other variables remain fixed.

  1. Written in scientific notation, 0.000060 x is
    B. 6.0 x 10-5 s
  2. When studying a molecule, a chemist might make a model of the molecule to

B. help visualize the molecule

  1. The maximum depth of a certain lade is 244 m. What is the depth of the lake in kilometers?

B. 0.244 km

Explaining Key Ideas

  1. Do scientific laws ever change? Explain.

Yes they can change if a new discovery cannot be predicted by a repeated experiments then the law may need to be modified to explain the new discovery.

  1. Explain whether or not scientific methods are sets of procedures that scientists follow.

They are not exact sets of procedures, they are only guidelines.

  1. Which variable is the dependent variable, and which variable is the independent variable?

Dependent variable:  temperature
Independent variable: time

  1. Why as this data presented in a line graph?

Because the temperature changed continuously with time during the experiment.

Critical Thinking

  1. Applying Ideas Today, scientists must search through scientific journals before performing an experiment or making methodical observations. Where would this step take place in a diagram of scientific methods?

Research and Data Collection step.

  1. Evaluating Assumptions At an air show, you are watching a group of sky divers when a friend says, “We learned in science class that things fall to Earth because of the law of gravitation.” What is wrong with your friend’s statement? Explain your reasoning.

The law of gravitation states that objects fall to the Earth and how to calculate, but it does not explain WHY.

 

  1. Applying Concepts You report that a friend can go exactly 500 m on a bicycle in 39.46 s. But your stopwatch runs 2 s fast. Explain how your stopwatch affects the accuracy and precision of your measurement.

Because your stopwatch runs fast the time you measure is not accurate. However your watch can measure somewhat precise.

 

Section 1

  1. air mass: a huge body of air that has similar temperature, humidity, and air pressure throughout
  2. anticyclone: a high-pressure system of dry air
  3. continental: a dry air mass that forms over land
  4. cyclone: a swirling center of low air pressure
  5. front: the boundary where unlike air masses meet but do not mix
  6. maritime:  a humid air mass that forms over oceans
  7. occluded:  cut off, as in a front where warm air mass is caught between two cooler air masses
  8. polar:  a cold air mass that forms north of 50o north latitude or south of 50o south latitude and has high air pressure
  9. tropical a warm air mass that forms in the tropics and has low air pressure

Section 2

  1. evacuate: to move away from an area temporarily to avoid hurricane conditions
  2. hurricane: a tropical storm that has winds of about 119 kilometers per hour or higher
  3. lightning: a sudden spark, or energy discharge, caused when electrical charges jump between parts of a cloud, between nearby clouds, or between a cloud and the ground
  4. storm:  a violent disturbance in the atmosphere
  5. storm surge:  a “dome” of water that sweeps across the coast where a hurricane lands.
  6. thunderstorm:  a small storm accompanied by heavy precipitation and frequent thunder and lightning
  7. tornado: a rapidly whirling, funnel-shaped cloud that reaches down from a storm cloud to touch Earth’s surface.

Section 3

  1. isobar: a line on a weather map that joins places that have the same air pressure
  2. isotherm: a line on a weather map that joins places that have the same temperature
  3. meteorologist: a scientist who studies the causes of weather and tries to predict it

 

Section 1

  1. climate:  the average year-after-year conditions of temperature, precipitation, winds, and clouds in an area
  2. continental climate: the climate of the centers of continents, with cold winters and warm or hot summers
  3. leeward:  the side of a mountain range that faces away from the oncoming wind
  4. marine climate:  the climate of some coastal regions, with relatively warm winters and cool summers
  5. microclimate: climate conditions within a small area that differ from those in the surrounding area
  6. monsoon: sea or land breeze over a large region that changes direction with the seasons
  7. polar zone:  the areas near both poles, from about 66.5o to 90 o north and 66.5 o  to 90o south latitudes
  8. temperate zone: the areas between the tropical and polar zones, from about 23.5 o to 66.5 o north and 23.5 o to 66.5 o south latitude
  9. tropical zone:  the area near the equator, between about 23.5 o north latitude and 23.5o south latitude
  10. windward: the side of a mountain range that faces the oncoming wind

Section 2

  1. desert: an arid region that on average receives less than 25 centimeters of rain a year. 
  2. humid subtropical: a wet and warm climate found on the edges of the tropics
  3. permafrost: permanently frozen soil found in the tundra climate region
  4. rain forest: a forest in the tropical wet climate zone in which large amounts of rain fall year-round
  5. savanna:  a tropical grassland with scattered clumps of trees
  6. steppe:  a prairie or grassland found in the semiarid climate region
  7. subarctic:  a climate zone that lies north of the humid continental climates, with short, cool summers and long, cold winters
  8. tundra:  a polar climate region, found across northern Alaska, Canada, and Russia with short, cool summers and bitterly cold winters

Section 3

  1. ice age: time in the past when continental glaciers covered large parts of Earth’s surface
  2. sunspot: a dark area of gas on the sun’s surface that is cooler than the surrounding gases

Section 4

  1. chlorofluorocarbon: chlorine compounds that are the main cause of ozone depletion
  2. El Nino:  A climate event that occurs every two to seven years in the Pacific Ocean, during which winds shift and push warm water toward the coast of South America
  3. global warming: a gradual increase in the temperature of Earth’s atmosphere
  4. greenhouse gas: gases in the atmosphere, such as carbon dioxide, that trap solar energy
  5. La Nina: a climate event in the eastern Pacific Ocean in which surface waters are colder than normal.

 

Explanation of scientific terms and definitions

 

Section 1

  1. combustion: the process of burning a fuel
  2. energy transformation: a change from one form of energy to another
  3. fossil fuel: an energy-rich substance (such as coal, oil or natural gas) formed from the remain of organisms
  4. fuel: a substance that provides energy as the result of a chemical change
  5. hydrocarbon: an energy-rich chemical compound that contains carbon and hydrogen atoms
  6. petrochemical: a compound made from oil
  7. petroleum: liquid fossil fuel; oil
  8. refinery: a factory in which crude oil is heated an separated into fuels and other products.

Section 2

  1. biomass fuel: fuel made from living things
  2. gasohol: a mixture of gasoline and alcohol
  3. geothermal energy: heat from Earth’s interior
  4. hydroelectric power: electricity produced using the energy of flowing water
  5. solar energy:  energy from the sun

Section 3

  1. control rod:  a cadmium rod used in a nuclear reactor to absorb neutrons from fission reactions
  2. fuel rod: a uranium rod that undergoes fission in a nuclear reaction
  3. meltdown: a dangerous condition in which fuel rods inside a nuclear reactor melt
  4. nuclear fission:  the splitting of an atom’s nucleus into two smaller nuclei and neutrons
  5. nuclear fusion: the combining of two atomic nuclei to produce a single larger nucleus and much energy
  6. nucleus:  the central core of an atom that contains the protons and neutrons;
  7. reactor vessel:  the part of a nuclear reactor where nuclear fission occurs

Section 4

  1. efficiency: the percentage of energy that is used to perform work
  2. energy conservation: the practice of reducing energy use
  3. insulation: material that blocks heat transfer between the air inside and outside a building

 

Section 1

  1. electromagnetic waves: waves that can transfer electric and magnetic energy through the vacuum of space
  2. greenhouse effect: the process by which heat is trapped in the atmosphere by water vapor, carbon dioxide, methane, and other gases that form a “blanket” around Earth; the trapping of heat by a planet’s atmosphere
  3. infrared radiation: electromagnetic waves with wavelengths that are longer than visible light but shorter than microwaves
  4. radiation:  the direct transfer of energy through space by electromagnetic waves
  5. scattering:  reflection of light in all directions
  6. ultraviolet radiation:  electromagnetic waves with wavelengths that are shorter than visible light but longer than X-rays

Section 2

  1. conduction:  the direct transfer of thermal energy from one substance to another substance that it is touching
  2. convection:  the transfer of thermal energy by the movement of a fluid
  3. convection currents:  the movement of fluid, caused by differences in temperature, that transfers heat from one part of the fluid to another
  4. heat: the transfer of thermal energy from one object to another because of a difference in temperature
  5. temperature: a measure of how hot or cold an object is compared to a reference point
  6. thermal energy: the total energy of motion in the particles of a substance
  7. thermometer: an instrument used to measure temperature, consisting of a thin glass tube with a bulb on one end that contains a liquid (usually mercury or alcohol).

Section 3

  1. anemometer: an instrument used to measure wind speed
  2. Coriolis effect: the effect of Earth’s rotation on the direction of winds and currents
  3. global winds:  winds that blow steadily from specific directions over long distances
  4. jet stream:  bands of high-speed winds about 10 kilometers above Earth’s surface
  5. land breeze: the flow of air from land to a body of water
  6. latitude: the distance in degrees north or south of the equator
  7. local winds:  winds that blow over short distances
  8. sea breeze: the flow of cooler air from over an ocean or lake toward land
  9. wind:  the horizontal movement of air from an area of high pressure to an area of lower pressure
  10. wind-chill factor: a measure of cooling combining with temperature with wind speed.

Section 4

  1. cirrus: wispy, feathery, clouds made mostly of ice crystals that form at high levels
  2. condensation:  the process by which molecules of water vapor in the air become liquid water
  3. cumulus: fluffy, white clouds, usually with flat bottoms, that look like rounded piles of cotton
  4. dew point: the temperature at which condensation begins
  5. evaporation: the process by which water molecules in liquid water escape into the air as water vapor
  6. humidity:  the amount of water vapor in a given volume of air
  7. pychrometer: an instrument used to measure relative humidity, consisting of a wet-bulb thermometer and a dry-bulb thermometer
  8. relative humidity:  the percentage of water vapor in the air compared to the maximum amount of water vapor that air can contain at a particular temperature
  9. stratus:  clouds that form in flat layers and often cover much of the sky
  10. water cycle:  the continual movement of water among Earth’s atmosphere, oceans, and land surface through evaporation, condensation, and precipitation

Section 5

  1. cloud seeding: process of producing rain during droughts by sprinkling silver iodide crystals and dry ice into clouds from airplanes
  2. drought: a long period of low precipitation
  3. precipitation: any form of water that falls from clouds and reaches Earth’s surface
  4. rain gauge: an instrument used to measure precipitation

 

Source :

http://kjpederson.wikispaces.com/file/view/Chapter1+Terms+with+definitions.doc

http://kjpederson.wikispaces.com/file/view/Chapter+6+Terms.doc

http://kjpederson.wikispaces.com/file/view/Physical+Science-notes+Chapter+3.doc

http://kjpederson.wikispaces.com/file/view/Chapter+7+Terms+with+definitions.doc

http://kjpederson.wikispaces.com/file/view/Chapter+12+Terms+with+definitions.doc

http://kjpederson.wikispaces.com/file/view/Chapter+10+terms+with+definitions.doc

http://kjpederson.wikispaces.com/file/view/Chapter+13+Terms+with+definitions.doc

http://kjpederson.wikispaces.com/file/view/Chapter+2+Terms+with+definitions.doc

http://kjpederson.wikispaces.com/file/view/Physcial+Science+Chapter+2+Terms.doc

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http://kjpederson.wikispaces.com/file/view/Physical+Science-notes+chapter+1.doc

http://kjpederson.wikispaces.com/file/view/Physical+Science-Chapter+4+section+review.doc

http://kjpederson.wikispaces.com/file/view/Physical+Science+End+of+Chapter+Questions+with+answers.doc

http://kjpederson.wikispaces.com/file/view/Chapter%2017%20Terms%20with%20definitions.doc/202707576/Chapter%2017%20Terms%20with%20definitions.doc

http://kjpederson.wikispaces.com/file/view/Chapter%2018%20Terms%20with%20definitions.doc/215444498/Chapter%2018%20Terms%20with%20definitions.doc

http://kjpederson.wikispaces.com/file/view/Chapter%2011%20Terms%20with%20definitions.doc/191157722/Chapter%2011%20Terms%20with%20definitions.doc

http://kjpederson.wikispaces.com/file/view/Chapter%2016%20Terms%20with%20definitions.doc/202502644/Chapter%2016%20Terms%20with%20definitions.doc

 

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