Vocabulary Notes
Atom - "the building blocks of matter"; the smallest particle of
an element that is still that element. Atoms are
electrically neutral (# of p+ = # e-)
Subatomic
Particle
Symbol
Location
Electrical
Charge
Mass
n0
In the
nucleus
0
1
Proton
p+
In the
nucleus
+
1
Electron
e-
"Shells"
around
the nucleus
-
1/1800
NUCLEONS
Neutron
Element - a substance made of only one kind of atom; all the
atom's of the element have the same # of p+ in
their nuclei.
Atomic Number - the # of p+ in the nucleus.
Ion - an atom that has an unbalanced proportion of p+ and
e- (i.e. there are extra or missing e-).
M
re e
Mo
:
sp
L es
+
or
e
p+
:L
e
ss
e-
Atomic Mass - the total # of p+ and n0; typically the
mass is average of the masses element's isotopes.
Isotope - atoms of the same element that
have different amounts of n0 in their
nucleus.
Isotope {H-1
Notation
H-2
H-3
Vocabulary Notes
Compound - a substance made of two or more
DIFFERENT atoms, chemically combined in
a fixed proportion.
Molecule (Molecular) a substance made of two
or more of the SAME or
DIFFERENT atoms.
Ionic a substance made of two
or more different ions
through the exchange of
e-.
Atoms combine
by sharing e- in
order to complete
their outer shell.
**All compounds can be molecules,
BUT not all molecules are compounds.**
Chemical Formula - combination of letters and numbers
that tells you what kinds of atoms
and the amount of each atom are in
the compound.
H2 O
C6H12O8
H2SO-4
Dihydrogen
Sucrose
oxide (a.k.a. water) Sugar
Sulfuric
acid
1 hydrogen
2 oxygens
2
1
4
7
3 atoms
6 carbons
12 hydrogens
6 oxygens
24 atoms
hydrogens
sulfur
oxygens
atoms