Atom
The smallest particle into which an element can be divided
Boiling point
The temperature at which a liquid boils and becomes a gas
Chemical change
A change that occurs when a substance is changed into one or more entirely new substances with different properties
Chemical property
A property of matter that describes a substance based on its ability to change into a new substance with different properties
Conductivity
The ability of a substance to transmit heat, electricity, or sound
Density
The amount of matter in a given space
Physical change
A change that affects one or more physical properties of a substance
Physical property
A property of matter that can be observed or measured without changing the identity of the matter
Mass
the amount of matter something has
volume
the amount of space something takes up
states of matter
the different ways a sample of matter can appear due to how fast and far apart the particles are
solid (particle behavior)
close, vibrating particles; coldest state of matter
liquid (particle behavior)
particles slip past each other
gas (particle behavior)
particles take up all the space available to them; particles act crazy
plasma
a gas that has been electrified or ionized
solid (volume/shape)
matter with definite volume and shape
liquid (volume/shape)
matter with definite volume but indefinite shape
gas (volume/shape)
matter with indefinite volume and shape
melting
solid turns to liquid
freezing
liquid turns to solid
vaporization
liquid becomes a gas
boiling
liquid becomes a gas at a specific temperature
evaporation
surface liquid particles gain energy to become a gas
condensation
gas becomes a liquid
sublimation
solid becomes a gas
phase change
when matter goes from one state to another because energy either enters or exits its particles
exothermic
describing a phase change when energy is lost or exits the particles
endothermic
describing a phase change when energy is gained or enters the particles
a flatter, more horizontal line on a phase change graph
shows that the matter is using the energy to change from one state to another and not to raise its temperature
pure substance
a type of matter where all of the particles are the same.
element
the simplest form of matter; pure substance where all atoms are the same
compound
a pure substance made up of more than one element chemically combined
separating an element
it can't be done
separating a compound
can only be separated chemically
separating a mixture
can be done physically and chemically
3 types of elements
metal, nonmetal, metalloids
metals on periodic table
to the left of the staircase
nonmetal on periodic table
to the right of the staircase
metalloids on periodic table
two sides of a the box will touch the staircase
properties of metals
shiny, malleable, ductile, good conductors, mostly solids at room temperature
properties of nonmetals
brittle, dull, poor conductors, about half are gases at room temperature
properties of metalloids
semiconductors, have some properties of metals and nonmetals at same time
malleability
the ability to be pounded or shaped without breaking
ductility
the ability to be pulled thin into wires
solubility
the ability to break into extremely small pieces when put into another substance
reactivity
the ability of a substance to combine with another substance to make something new
mixture
two or more substance combined using physical forces
homogeneous
describes something that looks the same throughout
heterogeneous
describes something that looks like it is made of different things
molecule
2 or more atoms chemically combined
elements after they combine
lose their characteristics and gain new ones
elements after the mix
keep their characteristics
proton (purpose)
determines which element is which
proton (charge)
positive subatomic particle
atomic number
number of protons
neutron (charge)
neutral
neutron (purpose)
keeps the protons from repelling
mass number
number of protons and neutrons in an atom's nucleus
ion
a charged particle
number of electrons versus number of protons
determines the charge of an atom or ion
# of protons - # of electrons = 0
neutral atom
# of protons - # of electrons ? +1
cation
# of protons - # of electrons ? -1
anion
electron (purpose)
determine charge of atom; only part involved in bonding
ionic compound
between metals and nonmetals, dissolve in water, conductive, high melting and boiling points, crystal structure
covalent compound
between nonmetals, insoluble in water, flammable, low melting and boiling points
isotopes
any versions of an atom with the same number of protons but different numbers of neutrons