Download Atomic Theory- 1. Matter is composed of tiny, indivisible particles

9.1
Atomic Theory1. Matter is composed of tiny, indivisible particles
called atoms.
2. An element is composed of one type of atom.
Properties of atoms are identical to each other.
3. A compound contains two or more different
elements. The relative number of atoms of each
element in a compound is the same.
4. Atoms don’t change their identities in chemical
reactions.-just rearranged.
http://www.youtube.com/watch?v=ZnKqiojoFJU
Three subatomic particles make up an atom;
Type
Proton
Neutron
Electron
Charge Mass
+1
1.673 x
10-24amu
No
1.65 x
charge 10-24amu
location
Nucleus
-1
Electron
Cloud
9.109 x
10-28amu
Nucleus
Strong nuclear force- holds nucleus together
even though protons try to repel.
Atomic number- number of protons in the
nucleus. Gives elements their identity. Same as
#of electrons
Mass number or Atomic mass- number of
protons plus neutrons. (isotope= same number
of protons, different number of neutrons)
Nucleus- positively charged
• Relative mass- 10,000
• Diameter= 10-15 meters 100,000 times smaller
than the electron cloud. Relative size = 1
Electron cloud- negatively charged
• Relative mass- 1
• Diameter- 10-10 –(100,000 larger than the
nucleus) Relative size = 100,000
Periodic table- Page 225
Periods- horizontal row
Group- vertical column
Metals- shiny, opaque, good conductor of heat and
electricity, malleable
Nonmetals- poor conductors, brittle, dull
Metalloids- properties of both
http://www.pbs.org/wgbh/nova/physics/cern.h
tml
1.Assignment READ 9.1 and then do
Do a/b questions page 223.
Do page 237, Solving Problems 1-6
2.Assignment- read 9.2Do #s 1-4 page 228
do #s 7-10-Solving Problems p.237