| Term | Definition |
|---|
| grams | unit of measurement for mass |
| g/cm3 | unit of measurement for density (name abbreviation) |
| liters | unit of measurement for liquid volume |
| Newtons | unit of measurement for weight |
| amu | unit of measurement for atomic mass (name abbreviation) |
| cm3 | unit of measurement for solid volume (name abbreviation) |
| meters | unit of measurement fro distance |
| mass | amount of matter in an object |
| triple beam balance | instrument used to measure mass |
| volume | amount of space that matter occupies |
| weight | measure of the force of gravity on an object |
| spring scale | instrument used to measure weight |
| solid, liquid, gas, plasma | four states of matter |
| freezing | when matter changes from a liquid to a solid |
| sublimation | when matter changes from a solid to a gas |
| boiling point | the point at which an entire substance vaporizes |
| periods | the rows of the periodic table are called ______ |
| groups | the columns of the periodic table are called ______ |
| scientific method | posing questions, developing hypotheses, designing experiments, collecting and interpreting data, drawing conclusions, and communicating ideas and results |
| manipulated variable | the variable that is changed |
| responding variable | the variable that changes because of the manipulated variable |
| physical change | a change that alters the appearance of a substance but does not change the substance |
| chemical change | a change that produces one or more new substances |
| physical properties | characteristics that can be observed without changing the substance |
| chemical properties | characteristics that describe their abilities to change into other substances |
| valence electrons | electrons that are in the highest energy level of an atom and that are involved in chemical reactions |
| protons | positively charged particles of the nucleus |
| neutron | electrically neutral particle in the nucleus |
| electrons | negatively charged particles |
| elements | pure substances that cannot be broken down into any other substances |
| atomic number | number of protons in the nucleus |
| atomic mass | the sum of the protons and neutrons in the nucleus |
| isotopes | atoms with the same number of protons and a different number of neutrons |
| alkali metals | group 1, most reactive metals |
| alkaline earth metals | group 2 |
| transition metals | groups 3-12 |
| mixed metals | group 13, least reactive metals |
| carbon group | group 14 |
| nitrogen group | group 15 |
| oxygen group | group 16 |
| halogen group | group 17, most reactive nonmetals |
| noble gases | group 18, very nonreactive |
| synthesis | type of chemical reaction where two or more simple substances combine to form a new, more complex substance |
| decomposition | a chemical reaction that breaks down compounds into simpler products |
| single replacement | a chemical reaction where one element replaces another in a compound |
| double replacement | a chemical reaction where two elements in different compounds trade places |
| concentration | the amount of a substance in a given volume |
| catalyst | a material that increases the rate of a reaction by lowering the activation energy |
| enzymes | biological catalysts |
| inhibitor | a material used to decrease the rate of a reaction |
| solvent | part of solution present in the largest amount |
| solute | part of solution present in the smallest amount |
| solution | a well-mixed mixture that contains a solvent and a solute |
| colloid | a mixture containing small, undissolved particles that do not settle out |
| suspension | mixture in which particles can be seen and easily separated |
| activation energy | minimum amount of energy needed to start a chemical reaction |
| acid | a substance that tastes sour, reacts with metals and carbonates, and turns blue litmus paper red |
| indicator | a compound that changes color when in contact with an acid or base |
| base | a substance that tastes bitter, feels slippery, and turns red litmus paper blue |
| hydrogen | An acid produces ______ ions in water |
| hydroxide | A base produces ______ ions in water |
| pH scale | a range of values from 0 to 14 that expresses the concentration of hydrogen ions in a solution |
| neutralization | a reaction between an acid and a base that produces a salt and water |
| reactants | substance(s) you have at the beginning of a chemical reaction |
| products | what the substance(s) produces in a chemical reaction |
| endothermic reaction | a reaction where energy is absorbed |
| exothermic reaction | a reaction where energy is released in a form of heat |
| heterogeneous mixture | mixture where you can see the different parts (answer is not suspension) |
| homogeneous mixture | mixture that is so evenly mixed that you cannot see the different parts (the answer is not solution) |
| melting | when a solid changes into a liquid |
| condensation | when a gas changes into a liquid |
| vaporization | when a liquid changes into a gas |
| motion | An object is in _____ if its distance from another object is changing |
| reference point | a place or object used for comparison to determine if something is in motion |
| SI units | used by scientists to describe the distance an object moves |
| v=d/t | equation for velocity/speed (abbreviation) |
| speed | the distance the object travels per unit of time |
| velocity | speed in a given direction |
| slope | the steepness of a line on a graph |
| acceleration | the rate at which velocity changes |
| force | a push or pull |
| newton | SI unit by which the strength of a force is measured by |
| net force | the combination of all forces acting on an object |
| friction | the force that two surfaces exert on each other when they rub against each other |
| hardness and type | two factors strength of friction depend on |
| static friction | friction that acts on objects that are not moving |
| sliding friction | friction when two solid surfaces slide over each other |
| rolling friction | when an object rolls across a surface |
| fluid friction | when a solid object moves through a fluid |
| gravity | force that pulls objects toward each other |
| mass and distance | two factors that affect gravitational attraction between objects |
| free fall | when the only force acting on an object is gravity |
| air resistance | type of fluid friction that objects falling through air experience |
| terminal velocity | the greatest velocity a falling object reaches |
| projectile | an object that is thrown |
| Newton's first law | states that an object at rest will remain at rest, and an object moving at a constant velocity will continue moving at a constant velocity, unless it is acted upon by an unbalanced force |
| inertia | the tendency of an object to resist a change in motion |
| Newton's second law | states that acceleration depends on the object's mass and on the net force acting on the object |
| a=f/m | described by Newton's second law (abbreviation) |
| Newton's third law | states that if one object exerts a force on another object, then the second object exerts a force of equal strength in the opposite direction on the first object |
| momentum | a characteristic of a moving object that is related to the mass and the velocity of the object |
| law of conservation of momentum | states that, in the absence of outside forces, the total momentum of objects that interact does not change |
| work | when you exert a force on an object that causes the object to move some distance |
| joule | A unit of work equal to one newton-meter |
| power | the rate at which work is done |
| energy | the ability to do work or cause change |
| kinetic energy | the energy and object has due to its motion |
| ke=1/2mv2 | equation for kinetic energy (abbreviation) |
| potential energy | stored energy that results from the position or shape of an object |
| gravitational potential energy | potential energy related to an objects height |
| mechanical energy | the form of energy associated with the position and motion of an object |
| thermal energy | the total potential and kinetic energy of the particles in an object |
| electrical energy | the energy of electric charges |
| chemical energy | potential energy stored in the chemical bonds that hold chemical compounds together |
| nuclear | stored in the nucleus of an atom |
| temperature | the measure of the average kinetic energy of the individual particles in matter |
| Fahrenheit scale | The temperature scale on which water freezes at 32 degrees and boils at 212 degrees |
| Celsius scale | The temperature scale on which water freezes at 0 degrees and boils at 100 degrees |
| Kelvin | The temperature scale on which zero is the temperature at which no more energy can be removed from matter |
| absolute zero | 0 on the Kelvin scale ,The temperature at which no more energy can be removed from matter |
| heat | Thermal energy that is transferred from matter at a higher temperature to matter at a lower temperature |
| specific heat | The amount of heat required to raise the temperature of 1 kilogram of a material by 1 kelvin |
| conduction | The transfer of heat from one particle of matter to another |
| convection | The transfer of heat by the movement of currents within a fluid |
| convection current | A current caused by the rising of heated fluid and sinking of cooled fluid |
| radiation | the transfer of energy by electromagnetic waves |
| conductor | a material that conducts heat well |
| insulator | a material that does not conduct heat well |
| change of state | the physical change from one state of matter to another |
| thermal expansion | the expanding of matter when it is heated |
| wave | a disturbance that transfers energy from place to place |
| medium | the material through which a wave travels |
| mechanical waves | waves that require a medium to travel through |
| vibration | a repeated back-and-forth or up-and-down motion |
| transverse waves | waves that move the medium at right angles to the direction in which the waves travel |
| crest | the highest part of a transverse wave |
| trough | the lowest part of a transverse wave |
| longitudinal waves | waves that move the medium parallel to the direction in which waves travel |
| compressions | the parts where the coils are close together in a longitudinal wave |
| rarefactions | the parts where the coils are spread out in a longitudinal wave |
| amplitude | the maximum distance that the particles of the medium carrying the wave move away from their rest position |
| wavelength | the distance between two corresponding parts of a wave |
| frequency | the number of complete waves that pass a given point in a certain amount of time |
| hertz | unit of measurement for frequency |
| reflection | The bouncing back of an object or a wave when it hits a surface through which it cannot pass |
| law of reflection | states that the angle of incidence equals the angle of reflection |
| refraction | the bending of waves due to a change in speed |
| diffraction | The bending of waves as they move around a barrier or pass through an opening |
| interference | interaction between waves that meet |
| constructive interference | The interference that occurs when waves combine to make a wave with a larger amplitude |
| destructive interference | The interference that occurs when two waves combine to make a wave with a smaller amplitude |
| standing wave | a wave that appears to stand in one place |
| nodes | a point of zero amplitude on a standing wave |
| antinodes | the points of maximum amplitude on a standing wave |
| resonance | an increase in the amplitude of a vibration that occurs when external vibrations match and object's natural frequency |
| echo | a reflected sound wave |
| elasticity | the ability of a material to bounce back after being disturbed |
| loudness | your perception of the energy of a sound |
| intensity | the amount of energy a sound wave carries per second through a unit area |
| decibel | unit for measuring loudness |
| pitch | a description of how high or low the sound seems to a person |
| ultrasound | Sound waves with frequencies above the normal human range of hearing |
| infrasound | sounds with frequencies below the human range of hearing |
| larynx | voice box |
| Doppler effect | The change in frequency of a wave as its source moves in relation to an observer |
| music | a set of notes that combine in patterns that are pleasing |
| acoustics | the study of how sounds interact with each other and the environment |
| electromagnetic wave | a transverse wave that transfers electrical and magnetic energy |
| electromagnetic radiation | The energy transferred through space by electromagnetic waves |
| polarized light | Light that vibrates in only one direction |
| photoelectric effect | The ejection of electrons from a substance when light is shined on it |
| photon | each packet of light energy |
| electromagnetic spectrum | the complete range of electromagnetic waves placed in order of increasing frequency |
| radio waves | Electromagnetic waves with the longest wavelengths and lowest frequencies |
| microwaves | Radio waves with the shortest wavelengths and the highest frequencies |
| radar | A system that uses reflected radio waves to detect objects and measure their distance and speed |
| infrared rays | Electromagnetic waves with wavelengths shorter than radio waves, but longer than visible light |
| thermogram | an image that shows regions of different temperatures in different colors |
| visible light | electromagnetic waves that you can see |
| ultraviolet rays | Electromagnetic waves with wavelengths shorter than visible light, but longer than X-rays |
| x-rays | Electromagnetic waves with wavelengths shorter than ultraviolet rays, but longer than gamma rays |
| gamma rays | Electromagnetic waves with the shortest wavelengths and highest frequencies |
| illuminated | an object that can be seen because it reflects light |
| luminous | an object that gives off its own light |
| spectroscope | instrument used to view the different colors of light produced by a light bulb |
| incandescent light | a light bulb that glows when a filament inside it gets white hot |
| tungsten-halogen bulb | a bulb that has a tungsten filament and contains a halogen gas |
| fluorescent light | a bulb that contains a gas and is coated on the inside with a powder |
| vapor light | a bulb that contains neon or argon gas and a small amount of sodium or mercury |
| neon light | a sealed glass tube that contains neon gas |
| transparent material | transmits most of the light that strikes it |
| translucent material | scatters light as it passes through |
| opaque material | reflects or absorbs all of the light that strikes it |
| primary colors | three colors that can combine to make any other color |
| secondary color | two primary colors combined in equal amounts |
| red, green, blue | three primary colors of light |
| complementary colors | any two colors that combine to form white light |
| pigments | colored substances that are used to color other materials |
| yellow, cyan, magenta | three primary colors of pigments |
| rays | straight lines that represent light rays |
| regular reflection | when parallel light rays hit a smooth surface |
| diffuse reflection | when parallel light rays hit a bumpy or uneven surface |
| plane mirror | a flat sheet of glass that has a smooth, sliver-colored coating on one side |
| image | a copy of an object formed by reflected or refracted rays of light |
| virtual image | an upright image that forms where light seems to come from |
| concave mirror | a mirror with a surface that curves inward |
| optical axis | an imaginary line that divides m mirror in half |
| focal point | the point at which rays parallel to the optical axis meet |
| real image | forms when rays actually meet |
| convex mirror | a mirror with a surface that curves outward |
| index of refraction | a measure of how much a ray of light bends when it enters that material |
| mirage | an image of a distant object caused by refraction of light |
| lens | a curved piece of glass or other transparent material that is used to refract light |
| convex lens | a lens that is thicker in the center than on the edges |
| concave lens | thinner in the center than at the edges |
| cornea | the transparent front surface that light enters the eye through |
| pupil | an opening through which light enters the inside of the eye |
| iris | a ring of muscle that contracts and expands to change the size of the pupil |
| retina | a layer of cells that lines the inside of the eyeball |
| rods | cells that contain a pigment that responds to small amounts of light |
| cones | cells that respond to color |
| optic nerve | Short, thick nerve that carries signals from the eye to the brain |
| nearsightedness | A condition that causes a person to see distant objects as blurry |
| farsightedness | A condition that causes a person to see nearby objects as blurry |
| magnet | any material that attracts iron |
| magnetic pole | the two ends of a magnet |
| magnetic force | the attraction or repulsion between magnetic poles |
| magnetic field | the area of magnetic force around a magnet |
| atom | smallest particle of an element |
| magnetic domain | a grouping of atoms that have their magnetic fields aligned |
| ferromagnetic material | a material that shows strong magnetic properties |
| iron, nickel, cobalt, gadolinium | common ferromagnetic materials in nature |
| temporary magnet | a magnet that easily loses its magnetism |
| permanent magnet | a magnet that keeps its magnetism for a long time |
| electric force | the attraction or repulsion between electric charges |
| static electricity | the buildup of charges on an object |
| conservation of charge | if one object gives up electrons, another object gains those electrons |
| induction | movement of electrons to one part of an object that is caused by the electric filed of a second object |
| static discharge | the loss of static electricity as electric charges transfer from one object to another |
| electric current | the continuous flow of electric charges through a material |
| electric circuit | a complete unbroken path through which electric charges can flow |
| voltage | the difference in electrical potential energy between two places in a circut |
| ohm | unit of measurement for resistance |
| electrochemical cell | a device that converts chemical energy into electrical energy |
| electrolyte | a substance that conducts electric current |
| terminal | part of electrode about the surface of the electrolyte |
| battery | a combination of two or more electrochemical cells in a series |
| wet cell | electromagnetic cell where electrolyte is liquid |
| dry cell | electromagnetic cell where electrolyte is a paste |
| series circuit | An electric circuit with a single path |
| ammeter | a device used to measure current |
| parallel circuit | An electric circuit with multiple paths |
Combine with other sets
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