Download Matter and Periodic Table Matter- anything that has mass and takes

Matter and Periodic Table
Matter- anything that has mass and takes up space
2 Categories:
1. Pure Substance- fixed composition
A. Elements- all atoms of a substance have the same
identity
* ~92 in nature
* 20 + synthetic
*Elements are represented with a chemical symbol Ex:
oxygen = O
B. Compounds- 2 or more elements combine in a fixed
portion
*represented with a chemical formula
*Ex: H2O
2. Mixtures- 2 or more substances
A. Heterogeneous- different substances can be
distinguished Ex: taco, garden salad and cereal
B. Homogeneous- 2 or more gases, liquids or solids
blended evenly Ex: Sugar water, Kool Aid
All matter is made up of Atoms
Atoms
* smallest particle of matter that contain the characteristics
of an element.
Nucleus-center of the atom; contains protons and neutrons
A. Proton - positive charge
- Identifies the atom
- Atomic # = # of protons
B. Neutron- no charge
- Mass atom = protons + neutrons
Electrons are located in the electron cloud.
Electrons- negative charge
- Responsible for all bonding
- Found on energy levels
- Mass is so small it isn’t included in the mass
number
Example: atomic number = 57 and mass = 139
Protons=
Neutrons=
Electrons=
 17 protons and 18 neutrons
Electrons=
Mass=
Atomic Number =
-If two atoms of the same element have different number of
neutrons then it is an isotope.
Atomic Mass = found on the periodic table
= average of all isotopes masses
Changes the mass number but the atomic number remains
the same.
Ex: Carbon-14
Carbon -12
Mass = 14
Mass = 12
Protons = 6
Protons = 6
Neutrons = 14-6
Neutrons = 12-6
=8
=6
Periodic Table
*a method of displaying the chemical elements
How many natural elements exist?
How many synthetic elements exist?
*Scientist create new nuclei to make new elements.
Organization of the Periodic Table
Groups or Families:
- Columns of the periodic table
- Radius increases as you move down the PT
- Have similar properties because of the same # of
valence electrons
Period:
- Rows of the periodic table
- Each period represents a new energy level
Metals:
- Atoms lose electrons to form positive ions
- Located to the left of the metalloids
- Largest portion of the periodic table
- Good conductors
Nonmetals:
- Atoms that gain electrons for form negative ions
- Located to the right of the metalloids
- Bad conductors
Metalloids:
- A blend of metals and nonmetals
- Referred to as the staircase
- Displays characteristics of metals and nonmetals
92
U
Uranium
238
ProtonsNeutronsElectronsMass
Isotopes- 2 atoms of the same element that have different # of
neutrons but the same number of electrons
Helium-3
Helium- 4
Carbon-13
Carbon-14
Density
Density = Mass / Volume
cm3 or kg/L
Units: g/mL, g/
*Density is the same for a substance no matter how much you
have.
Example: 50g Copper Density = 8.92 g/ml
100 g Copper  Density = ________________
*Density can be used to identify a pure substance.
Example : Density of gold = 19.31 g/ml
You can use this information to test a piece of
jewelry to see if it is real or not!
Density of water = 1 g/ml
*If something is more dense than water it will
______________.
*If something is less dense than water it will
_______________.
Why does the egg float is the salt water (left) but sink in the
pure water?
Water Displacement- The
movement of water upward
when an object is place in a
container containing water.
Ex:
**What would be formed if a large section of an iceberg
broke off and landed in the ocean?