The Atom Flashcards
Electric Charge
a fundamental
property of matter that comes in
two types called positive and
negative.
Elementary Charge
the smallest unit of electric charge that is possible in ordinary matter; represented by the lowercase letter e
Neutral
a condition where the
total positive charge is canceled by
the total negative charge. Matter is
neutral most of the time.
Charged
a condition where
there is an excess of positive or
negative charge.
Static Electricity
the buildup of
either positive or negative charge;
made up of isolated, motionless
charges.
Electron
a particle with an
electric charge (-e) found inside of
atoms but outside the nucleus.
Proton
a particle with an electric
charge (+e) found in the nucleus of
atoms.
Neutron
a particle with zero
charge found in the nucleus of
atoms.
Nucleus
the tiny core at the
center of an atom containing most
of the atom’s mass and all of its
positive charge.
Atomic Number
the number of
protons in the nucleus. The atomic
number determines what element
the atom represents.
Isotopes
atoms of the same
element that have different
numbers of neutrons in the
nucleus.
Mass Number
the number of
protons plus the number of
neutrons in the nucleus.
Stable
a nucleus is stable if it
stays together.
Radioactive
a nucleus is
radioactive if it spontaneously
breaks up, emitting particles or
energy in the process.
Spectrum
the characteristic
colors of light given off or
absorbed by an element.
