Transcript 8th Grade Vocabulary (1)

TH
8
GRADE VOCABULARY
M.ESPINDOLA-MORENO
ATOM
•The smallest
particle of an
element made of
electrons, protons,
and neutrons.
PROTON
•
A positively
charged subatomic
particle of the
nucleus of an atom
that contributes
to the mass of
the atom.
ELECTRON
• A negatively
charged
subatomic
particle that
orbits the
atomic nucleus.
NEUTRON
• A subatomic particle of
the nucleus of an atom
without a charge that
contributes to the mass
of an atom.
Neutron
ELECTRON
CLOUD
• The area
surrounding the
nucleus of an atom
where the electrons
are found.
ELECTRICAL CHARGES
• A property of matter;
• Electrons are negative
• Protons are positive
• Neutrons are neutral
• The # of Protons and
Electrons determine the
charge of the atom.
ATOMIC MASS
•The mass of an atom,
equal to the # of
protons and neutrons
in the atom.
SUBATOMIC
PARTICLES
• Particles that are smaller
than the atom
• Protons
• Neutrons
• Electrons
ATOMIC NUMBER
• The number of protons in the nucleus
of an atom.
ENERGY LEVEL
• The fixed amount of
energy that a system
described by quantum
mechanics, such as a
molecule, atom, electron,
or nucleus, can have.
VALENCE ELECTRON
• The electrons in the outermost
energy level of an atom that
influence how an element will react
with other substances.
REACTIVITY
•Rate at which a
chemical substance
tends to undergo a
chemical reaction.
PERIODS
• Rows on the periodic table
• Read from left to right.
• There are 7 periods.
GROUPS
• Columns on the periodic table.
• Read from top to bottom,
• There are 18 groups.
ALKALI METALS
• Most reactive
metals on periodic
table.
• 1 valence electron
• Soft and shiny
AKALINE
METALS
EARTH
• Group 2
• Hard metals
• 2 valence electrons
HALOGENS
• Group 17
• 7 valence
electrons
• Very reactive
nonmetals
NOBLE GASES
METALS, NONMETALS,
METALLOIDS
ELEMENT
• An element is a
pure substance
that cannot be
separated into
simpler substances
by chemical means.
COMPOUND
•When two or
more elements
combine
chemically.
ORGANIC
COMPOUNDS
•Organic
compounds
contain
carbon…
SUBSCRIPT
•A # written
below and to
the right of
an atomic
symbol.
COEFFICIENT
•A # placed
in front of
a chemical
symbol or
formula.
CHEMICAL
FORMULA
• A shorthand
notation using
chemical
symbols and
numbers.