General Chemistry

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General Chemistry
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Chemistry

• Chemistry is the study of matter and how it
  changes and interacts with other matter

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Matter

• MATTER IS THE STUFF AROUND YOU Anything that
  takes up space or has a mass of any kind is
  matter.
• It can have PHYSICAL properties like different
  densities, melting points, boiling points,
  freezing points, color or smells.
• It can have CHEMICAL properties that define
  matter. A good example of chemical properties is
  the way elements combine with each other in
  reactions.

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States of Matter

• There are three main STATES of matter. SOLIDS,
  LIQUIDS, GASES.
• ELEMENTS and compounds can move from one phase to
  another when special physical forces are present
• ex. temperature
• Phase describes a PHYSICAL state of matter. If
  energy is added or taken away, the state of
  matter is changed.
• CHEMICAL FORCES DO NOT CHANGE THE STATE!

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What about plastic?

• Liquids
• What are some characteristics?
• Does plastic have any of these characteristics?
• Solids
• What are some characteristics?
• Does plastic have any of these characteristics?

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Atoms

• The smallest unit of matter having protons,
  electrons, and neutrons.
• Atoms are the basis for everything in the
  universe
• The center is the NUCLEUS.
• There are equal numbers of electrons and protons

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Periodic Table
Click here to print out your own copy of the
periodic table.
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Periods

• Each row is a different PERIODS
• All elements in a period have the same number of
  atomic SHELLS
• Every element in the top row (the first period)
  has one shell for its electrons.
• All of the elements in the second row (the second
  period) have two shells for their electrons.
• It continues down the periodic table like that.
  At this time, the maximum number of shells is
  seven.

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Groups

• When a column goes from top to bottom, it's
  called a GROUP
• The elements in a group have the same number of
  electrons in their outer shell
• Every element in the first column (group one) has
  one electron is its outer shell.
• Every element on the second column (group two)
  has two electrons in the outer shell.
• Count the columns and you'll know how many
  electrons are in the outer shell.
• The elements in between, in grey color, are
  TRANSITION elements.
• They have special electron rules.

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Exceptions

• Hydrogen can have the talents and electrons of
  two groups, one and seven.
• Hydrogen is sometimes missing an electron, and
  sometimes it has an extra.
• Helium can only have two electrons in its outer
  shell.
• It is still grouped with elements that have
  eight.

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Shells

• Shells surround the center of an atom.
• A shell is sometimes called orbital/energy level.
• Electrons live in shells.
• Not all shells hold the same number of electrons.
  

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Ions and bonding

• A normal atom has a NEUTRAL charge.
• has a number of electrons equal to the ATOMIC
  NUMBER.
• ION a charged atom. Missing or has extra
  electron(s)

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Compounds

• When two or more elements come together it is
  called a COMPOUND

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Compounds

• No matter what atoms are in a compound, they all
  want to be "happy".
• A happy atom is one with the right number of
  ELECTRONS in the outer ORBITAL
• That desire to be happy is why some elements only
  combine with a few other elements. Not all
  elements can make each other "happy".

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Ionic/Electrovalent Bonds

• ELECTROVALENCE is just another word for something
  that has given up its electron and become an ion
• When they are in the presence of other ions the
  electrovalent bonds are weaker
• Ionic bonds happen when electrons are given up by
  one atom to another

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Covalent Bonds

• Covalent compounds happen when the electrons are
  shared by the atoms

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When sodium atoms bond with one oxygen atom there
have to be two sodium atoms, each with an extra
electron. Each of these Sodium atoms gives oxygen
one electron, allowing Oxygen to have a full
shell with eight electrons.
Is this an example of Ionic or Covalent Bonding?
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Combinations

• Most compounds are made up of combinations of
  bonds

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Let's use carbon (C) as an example...

• There are a lot of carbon (C) atoms in the
  universe.
• The normal ones are called Carbon-12.
• Have 6 neutrons.
• Odd ones may have 7 or even 8 neutrons
• Carbon-14
• Has 8 neutrons (2 extra).
• C-14 is considered to be an isotope of the
  element of Carbon (C).
• When C-14 loses the extra neutrons in radioactive
  DECAY, it will become C-12.

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Carbon

• All plants have carbon as their most important
  element.
• Every living thing on Earth also needs carbon to
  survive.
• And it needs to be in plants before humans can do
  anything with it.
• Everything that is plastic has carbon in it.
• Like gasoline, plastic things are made from oil.
• That means carbon is also the most important
  element plastic.

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Reactions

• In a reaction, a chemical change must occur.
• Turn one compound into another.
• It could be ions, molecules, or pure atoms
• Single reactions often happen as part of a larger
  series of reactions.
• Take something as simple as moving your arm. The
  contraction of that muscle needs sugars for
  energy. Those sugars need metabolized
• A lot has to happen just to perform a simple task!

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Catalysts and Inhibitors

• Reactions need ACTIVATION ENERGY. A catalyst
  lowers the amount of energy needed.
• Maybe a molecule shifts it's structure.
• Maybe two molecules combine and they release
  energy.
• Inhibitors slow the rate of reaction.

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Stoichiometry

• STOICHIOMETRY is the part of chemistry that
  studies amounts of substances that are involved
  in reactions
• What do you measure?
• Mass of Reactants (chemicals before the reaction)
• Mass of Products (chemicals after the reaction)
• Chemical Equations
• Molecular Weights of Reactants and Products
• Formulas of Various Compounds

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Stoichiometry Example

• You start with two ions and wind up with an ionic
  compound (NaCl). Na Cl- --gt NaCl
• It takes one atom of sodium (Na) to combine with
  one atom of chlorine (Cl) to make the salt.
• With stoichiometry, you can determine amounts of
  substances needed to fulfill the requirements of
  the reaction.
• Stoichiometry will tell you that if you have ten
  million atoms of sodium (Na) and only one atom of
  chlorine (Cl) you can only make one molecule of
  Sodium chloride (NaCl). 10,000,000 Na 1 Cl-
  --gt NaCl 9,999,999 Na
• Nothing you can do will change that.

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Organic Chemistry

• The chemistry of the compounds of carbon
• Organic is a misleading name
• Today most carbon compounds are synthesized
• Usually from other organic compounds
• Petroleum
• Coal

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Carbon Compounds

• Why so special?
• Very, very many compounds
• Molecules can be large and complex
• Can attach themselves to one another to an extent
  not possible for atoms of any other element
• Each different arrangement of atoms corresponds
  to a different compound
• Each compound has its own set of chemical and
  physical properties.

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The Age of Carbon

• Organic Chemistry is immensely important to
  technology
• It is the chemistry of
• Dyes and drugs
• Paper and ink
• Paints and plastics!
• Gasoline and rubber tires
• Food and clothing
• Biology and medicine

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Plastics are polymers

• The most simple definition of a polymer is
  something made of many units.
• "MER" is Greek for "part."
• "POLY" is Greek for "many",
• The long chain of "mers" forms a "POLYMER."

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Think of a polymer as a chain.

• Each link of the chain is a monomer
• Usually carbon, hydrogen, oxygen, and/or silicon.
  
• To make the chain, many monomers are hooked or
  polymerized together.

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The Structure of Polymers

• Many common classes of polymers are composed of
  hydrocarbons.
• Carbon makes up the backbone
• Hydrogen atoms are bonded along the backbone.

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The Structure of Polymers

• There are polymers that contain only carbon and
  hydrogen.
• Polypropylene, polybutylene, polystyrene,
  polymethylpentene

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The Structure of Polymers

• Other elements can also be involved
• Polyvinyl chloride (PVC) contains chlorine
• Nylon contains nitrogen.
• Teflon contains fluorine
• Polyester and polycarbonates contain oxygen.

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Characteristics of Polymers

• 1) Polymers can be very resistant to chemicals.
• 2) Polymers can be both thermal and electrical
  insulators.
• 3) Generally, polymers are very light in weight
  with varying degrees of strength.
• 4) Polymers can be processed in various ways to
  produce thin fibers or very intricate parts.

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Isomers

• There are compounds with the same number of atoms
  but different shapes called ISOMERS.

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Carbon Compounds