Ch. 4 - Atomic Structure

Subatomic Particles

Subatomic Particles

POSIT IVECHARG E

PROT ONS

NEUT RALCHARG E

NEUT RONS

NUCLEUS

NEG AT IVE CHARG E

ELECT RONS

AT OM

Most of the atom’s mass.

NUCLEUS ELECTRONS

PROTONS NEUTRONS NEGATIVE CHARGE

POSITIVE CHARGE

NEUTRAL CHARGE

ATOM

QUARKSAtomic Numberequals the # of...

equal in a neutral atom

Subatomic Particles

Quarks

• component of protons & neutrons

• 6 types

• 3 quarks = 1 proton or 1 neutron

He

4 Atomic Structure Fundamentals found using the Periodic Table

1. Number of each subatomic particle 2. Number of valence (outer shell)

electrons = the column number I to VIII 3. Whether it is a metal, nonmetal or

semimetal in its elemental form 4. Whether it is monoatomic, diatomic or

other in its elemental form…Remember it is still a pure substance (element) and not called a compound

5 Atomic Structure Fundamentals found using the Periodic Table

Number of subatomic particles Number of valence (outer shell) electrons =

the column number I to VIII Whether it is a metal, nonmetal or semimetal

in its elemental form The oxidation state, or charge, of the ionized

form Whether it is monoatomic, diatomic or other

in its elemental form…it is still a pure substance (element) and not called a compound

# of Subatomic Particles…

p+ = atomic number n0 = mass # - p+

because mass of atom is p+ + n0

e- = p+ - charge

because charge of atom/ion is p+ - e-

Valence Electrons Number of Valence (Outer Shell)

Electrons = Columns number IA to VIIIA

Examples

H, Li, Na have 1 valence e-

O, S, and Se have 6 val e-

He, Ne, Ar, Kr have 8 val e-

Oxidation State

The oxidation state (or charge) of the ionized forms correspond to columns also

Oxidation States

+1 +2 +3 +/- 4 -3 -2 -1

0

Charges are positive when valence electrons are lost

Charges are negative when valence e-’s are gained

Metallic CharacterMetals (lose e-s)= to left of stairstep

Nonmetals (gain e-s) = H and to right of stairstep

Semimetals/metalloids = 7 elements touching stairstep

Diatomic Elements?

All elements are monoatomic (like Li, Mg, C, Se, etc) EXCEPT:

“Seven of 7 go to H eaven” are all

diatomic in elemental form = N2, O2, F2, Cl2, Br2, I2, and H2

Phosphorus is P4 and sulfur can be S or S8

Isotopes

Atoms of the same element (same atomic #) with different masses (thus different number of neutrons)

Most atoms exist with multiple isotope forms

Some isotopes are unstable/radioactive and decay to form new atoms

Band of Stability Graph

need more neutrons than protons as the atom gets bigger