Ch. 9 Stoichiometry

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Ch. 9 Stoichiometry

• Stoichiometry is a branch of chemistry that deals
  with the mass relationships of elements in
  compounds and the mass relationships between
  reactants and products in chemical reactions.
• 2 Types of Stoichiometry
• 1. Composition Stoichiometry is the mass
  relationships of elements in chemical compounds.
• Ex. Molar mass of Li is 6.941 grams

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• 2. Reaction Stoichiometry is the mass
  relationship among reactants and products of a
  chemical reaction.
• Ex. NaCl H2O ? HCl NaOH
• 58.44g 18.02g 36.46g 40.00g
• 4 Reaction Stoichiometry Problems
• 1. Mole to Mole
• 2. Mass to Mass
• 3. Mole to Mass
• 4. Mass to Mole

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• EXAMPLES ???
• Sample Problems 9.1 9.5
• Limiting Reactant is the reactant that limits the
  amount of the other reactants that can combine,
  and the amount of products formed in a chemical
  reaction.
• Excess Reactant is the substance that is not used
  up completely in a reaction.
• Ex. If a bus holds 50 people and 60 are waiting
  to ride the bus, 10 will be left in excess.
• Sample problems 9.6 9.7

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• Percent Yield is the ratio of the actual yield to
  theoretical yield times 100.
• (Actual yield / Theoretical yield) X 100
• Theoretical yield is the maximum amount of
  product that can be produced from a given amount
  of reactant.
• Actual yield is the measured amount of a product
  obtained from the product of a reaction.
• Sample Problem 9.8