Coral Bean Erythrina herbacea

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Coral Bean (Erythrina herbacea)
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Balancing Reactions

• Dr. Smith
• 2007

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Alchemy to Chemistry

• the phlogiston theory can be seen as the
  opposite of the modern "oxygen theory". The
  phlogiston theory states that all flammable
  materials contain phlogiston that is liberated in
  burning, leaving the "dephlogisticated" substance
  in its "true" calx form. In the modern
  understanding, on the other hand, flammable
  materials (or unrusted metals) are "deoxygenated"
  when in their pure form and become oxygenated
  when burned

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Law of Conservation of Mass

• Mikhail Lomonosov (1711-1765) Antoine Lavoisier
  (1743-1794)
• Matter can be neither created nor destroyed in a
  chemical process. The total amount of mass at
  the end of the reaction is the same as total mass
  at the beginning of the reaction

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Atomic Interpretation

• There must be the same number of atoms of each
  element on both sides of a reaction.
• Achieved by manipulation of coefficients in front
  of the formula for each chemical.

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NaOH H2SO4 gt Na2SO4 H2O
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2NaOH H2SO4 gt Na2SO4 2H2O
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Balancing by Inspection

• See which elements only occur in one compound on
  the reactant and the product sides of the
  reaction
• Balance these first
• Then work your way out to more frequently
  occurring elements

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C3H8 O2 gt CO2 H2O
C3H8 O2 gt 3CO2 H2O
C3H8 O2 gt 3CO2 4H2O
C3H8 5O2 gt 3CO2 4H2O
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Al ZnO gt Al2O3 Zn
2Al ZnO gt Al2O3 Zn
2Al 3ZnO gt Al2O3 Zn
2Al 3ZnO gt Al2O3 3Zn
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Fe O2 gt Fe2O3
2Fe O2 gt Fe2O3
2Fe 3/2 O2 gt Fe2O3
4Fe 3O2 gt 2Fe2O3
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Ba(OAc)2 H3PO4 gt Ba3(PO4)2 HOAc
3Ba(OAc)2 H3PO4 gt Ba3(PO4)2 HOAc
3Ba(OAc)2 2H3PO4 gt Ba3(PO4)2 HOAc
3Ba(OAc)2 2H3PO4 gt Ba3(PO4)2 6HOAc