Protons, Neutrons, and electrons
Subatomic Particles
The nucleus
Almost all the mass of the atom Radius is 1/10,000 the size of the radius of the atom
Atoms are electrically neutral because:
# of protons = # of electrons (e-) if electorally neutral
Isotopes
Same #p, different #n
They are the same element because same Z
different masses because different #n
Mass Number (A)
#p+#n=A
z + n=A
Ions
Charged particles formed when atom's gain or lose electrons
Cation
Positively charged ion
Anion
Negatively charged ion
Atomic mass =
fraction of isotope * mass of isotope
Artifical elements
Z > 92
Artificial elements do not have:
Atomic masses because thy have no naturally occurring isotopes
Elements within the same row:
are in the same period
Elements within the same column:
Similar chemical properties