Balancing Equations

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• Balancing Equations
• shows Law of Conservation of Matter
• atoms are not created or destroyed in a
  chemical reaction, only rearranged.
• Mass Reactants Mass Products

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• Writing Equations
• Elements Diatomic have subscript 2
• H2, N2, O2, F2, Cl2, Br2, I2
• 2. Compounds use Oxidation s (charges)
• to get subscripts (criss-cross reduce)
• Hydrogen chloride
• 3. Balance with coefficients in front
• Sodium Oxygen ? Sodium oxide

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• Examples
• Hydrogen Oxygen ? Water
• b. Sodium hydroxide Hydrogen chloride ?
  Sodium chloride Water

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• Magnesium Hydrogen chloride ?
• Magnesium chloride Hydrogen
• d. Hydrogen carbonate ?
• Water Carbon dioxide

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• II. Solutions
• A. Two Parts of a Solution
• solute smaller amount, is dissolved
• solvent larger amount, does the dissolving
• Since Ionic compounds have high M.P.s, solvents
  are covalent compounds.

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• Two types of Covalent Compounds/Solvents
• 1. Polar - example water
• a. share electrons unequally
• b. have small charges
• c. are poor conductors
• 2. Nonpolar examples oil, gasoline
• a. share electrons equally
• b. have no charges
• c. are nonconductors

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• B. Solubility amount that can be dissolved
• Depends on
• 1. Polarity like dissolves like
• charges mix ionic/polar
• noncharges mix nonpolar/nonpolar
• 2. Particle size (if solids)
• smaller dissolve better
• 3. Agitation (stirring or shaking)
• adds energy to molecules
• helps solids dissolve
• lets gases escape

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• 4. Pressure
• affects gases only
• pushes molecules into solution
• 5. Temperature
• adds energy to molecules
• heat helps solids dissolve better
• cold helps gases dissolve better

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• III. Electrolytes
• Ionic compounds separate into free ions
• with charges when dissolved in solutions
• Will conduct electricity
• Acids H1 nonmetal or polyatomic ion
• Properties
• 1. Sour taste
• 2. Turn litmus red
• 3. React with metals to form Hydrogen gas
• 4. Have low pH (0-6)

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• B. Bases metal or ammonium Hydroxide
• Properties
• 1. Bitter taste
• 2. Turn litmus blue
• 3. Feel slippery break down fat
• 4. Have high pH (8-14)
• pH power of Hydrogen Ion
• if H1 10-7, then pH 7 (neutral)

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• C. Salts any Ionic Compound
• that is not an acid or a base
• formed by neutralization reactions
• Acid Base ? Salt Water

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• Chemistry Test Next Week
• -Match Scientists with Atomic Discoveries
• (Dalton, Thomson, Rutherford, Bohr, Schrodinger)
• -Find Atomic , Mass, Oxidation ,
• protons, neutrons, electrons
• -Nuclear
• Write nuclear equations
• Know nuclear particles
• Identify fission or fusion
• Half-life problems

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• -Draw Bohr diagrams for atoms
• -Metal Nonmetal properties
• -Families of Elements Names Properties
• (Groups 1, 17, 18)
• -Identify Physical Chemical Changes
• -Properties of Ionic Covalent Compounds
• -Write formulas (know oxidation s)
• -Balance Equations (know diatomic elements)
• -Factors affecting Solubility/Read a Solubility
  Graph
• -Acid Base Properties