matter & energy test vocab Flashcards
(31 cards)
state the kinetic theory of matter
all matter is made up of atoms and molecules; these atoms and molecules act like tiny particles that are always in motion
rules for determining speed of particles are…
higher temps = faster particle speed; when at the same temp. more massive particles move slower and less massive particles move faster
name 3 basic phases of matter
solid, liquid, gas
define solids
particles vibrate back and forth in place; have a definite shape and volume; particles held together by strong forces of attraction; have a rigid structure and cant easily change position
define liquid
particles are closely packed but can slide past each other; definite volume but not shape; take the shape of their container; liquids flow freely - fluid- moving fast enough to overcome some of the forces of attraction between particles
define gases
particles in constant motion and far apart, don’t usually stick together; no definite shape or volume; move fast enough to overcome almost all the forces of attraction between particles; particles independent of one another; flow like liquids - both classified as fluids; gases change shape + volume; expand to fill a room
how are the diff types of matter classified
classified into phases by determining whether the shape + volume are definite or if they change
define plasma
most common phase of matter in universe; no definite shape or volume; composes 99% of all matter in the universe (stars); particles = electrically charged (ionized); require an energy source to exist ex: neon lights
what can gases not do that plasma can
gases cannot conduct a current like a plasma can
define energy
ability to change or move matter (do work)
define temperature
measure of how hot or cold smth is and a measure of the average kinetic energy of the particles or an object
more kinetic energy an object has…
higher the temp is
define thermal energy
total ke of particles of a substance
more ke =
higher total ke or thermal energy
define a change of state
when a substance is converted from one physical form to another
energy + to a substance =
particles move faster
energy removed to a substance=
particles move slower
define melting
changing solid into liquid; caused when heat is added to a solid; particles start to move faster w/more energy; temp this occurs at is called melting point; depends on pressure
define evaporation
changing liquid to gas; boiling is evaporation that occurs throughout a liquid at a specific temp +pressure; boiling pt is the temp where a liquid boils
define sublimation
changing of solid directly to gas wo/ever being a liquid; ex: dry ice to CO2 gas
define condensation
changing from gas to liquid; condensation point is the temp where gas becomes liquid
define freezing
changing a liquid to solid; freezing point is the temp where liquid becomes solid
define fundamental law of physical science
mass+energy are both conserved. neither mass nor energy can be created or destroyed
define law of conservation of mass
mass cant be created or destroyed
