Download Chemistry Notes Part 1

Chemistry Notes Part 1
• Greek Philosopher
• 4 Elements
Earth
Fire
Water
Air
Emphedocles
--•
Elements
•
Something that can not be
broken down into a simpler
form and maintain
characteristic properties
Made up of only ONE type of
atom
--Russian Scientist
Invented the periodic table of
elements
Only 50 known elements
1860s
Predicted new elements
• Now: 118 known elements
#1-92 occur naturally
Only 88 are naturally found on
earth
--• “Stuff” or “LEGOS®” of the
universe
Solid
Liquid
Gas
Plasma
BEC (Bose-Einstein Condensate)
--• Greek Philosopher
• Atom is “indivisible”
--• Basic unit of an element
--• Parts of an atom
Electrons: (-)
Orbits nucleus
≈.0000001 amu (atomic mass unit)
•
•
Dimitri Mendeleev
Matter
Democritus
Atom
Sub atomic particles
--Molecule
Element (Atomic) Number
Electron number of an atom
In nucleus
≈1 amu
•
•
•
•
≥ 2 atoms bonded together
Ex: H2O
Ex: O2
Ex: CO2
•
Atomic # = # of Protons
-------
• Atom is electrically neutral
# of electrons = # of protons
•
Atomic mass
Mass of protons and neutrons
--Atomic mass – atomic number=
# of neutrons
EX: O (Oxygen)
+=8
-=8
0 = 8 (16-8)
Ex: Fe (Iron)
Ex: Mg (Magnesium)
•
Neutron #
--Rows
Columns
Valence electrons
Protons: (+)
In nucleus
≈1 amu
Neutrons: (none)
• Periods
How many electron orbitals
(shells) an atom has
--• Groups of Families
• Have similar
characteristics and
properties
• Same # of valence
electrons
--• Outer electrons of an atom
• Important for + are responsible
for chemical reactions