Basic Chemistry

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Basic Chemistry
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What is Matter?

• Matter is anything that has mass and takes up
  space.
• Matter can be found in 4 distinct phases solid,
  liquid, gas, and plasma.
• Matter is composed of small units called atoms.

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What is an Atom?

• An atom is the basic unit of matter.
• It is composed of negatively charge electrons
  spinning around a nucleus containing positively
  charged protons and non charged neutrons.

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Atomic Number and Atomic Mass

• The atomic number of an atom is the number of
  protons it contains in its nucleus.
• Sometime it may also equal the number of its
  electrons.
• The atomic mass of an atom is the total number of
  its protons and neutrons.

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Chemical Elements

• Atoms have been grouped according to their atomic
  number and mass into units called elements.
• There are 109 of these elements known to man,
  which 90 of them occur naturally.
• These elements are represented by symbols.
• The Periodic Table contains the complete list of
  these elements.

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Periodic Table
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Chemical Compounds

• Are formed when 2 or more different elements
  combine.
• The upper example is a molecule of glucose while
  the lower one is 2 water molecules.

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What Holds Chemical Compounds Together?

• Atoms need to be stable.
• In order for this to occur they must completely
  fill their outer level of electrons.
• This usually requires 8.
• Most atoms are lacking anywhere from 1 to 7
  electrons.
• Hydrogen is lacking 7, while Chlorine is lacking
  1.

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Types of Chemical Bonds

• Ionic
• Covalent

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Ionic Bond

• This type of bond is formed when one element
  takes the electron it needs from another element.
• This causes one element to become a ion due to
  the loss of its electron and the other a negative
  - ion due to the gain of the electron.
• The bond is formed by the attraction of the
  element to the - element.
• Example 2Na ------gt Cl2- 2NaCl

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Covalent Bond

• This type of bond is formed by the sharing of
  electrons between different atoms.
• It is a strong bond.
• Examples 2H2 O2 ----gt 2H2O

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Structural Formula

• What is the C in the compound Alanine?
• What is the line represent between the C and C?
• What does the 2 and 3 represent?

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Chemical Reactions.

• 2H2 O2 ----gt 2H2O
• Chemical reactions like the one above contain two
  parts The reactants and the products.
• The reactants are on the left of the arrow, while
  the products are to the right.

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What is pH?

• pH is the negative log of the Hydrogen ions
  concentration in solution.
• Waters chemical formula is H2O. Or
• H-O-H.
• Water has the ability to split into 2 separate
  ions H and OH-.
• If these ions are in balance than the solutions
  pH is neutral or 7.

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pH Scale

• The pH scale is based on the number 10.
• 7 is the middle or neutral.
• Acids contain more H in solution than the OH-
  ions. Any number below 7 is considered acidic.
• Bases contain more OH- ions than H ions. Any
  number higher than 7 is considered a base.
• pH is a very important variable in all chemical
  reactions.

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pH Scale
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Problems

• If stomach acid has a pH of 1, and a person took
  a tums tablet which raised the pH to 3, how much
  was the increase in pH?
• What is acid rain?
• How would we make an acidic lake normal again?