Chapter Six

1
Chapter Six

• Acids, Bases, and Solutions

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Lesson 6-1

• Understanding Solutions

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6-1

• A suspension is where particles can easily be
  seen and easily separated by settling or
  filtration.
• Oil and Vinegar

oil
V
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6-1

• A solution is a well mixed mixture and has the
  same properties throughout.
• Salt and Water

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6-1

• Solutions and suspensions differ in the size of
  their particles and the way the parts of the
  mixture can separate.
• Solutions contain at least two parts For
  example, Salt Water.
• Solvent largest amount (water)
• Solute smallest amount dissolved by solvent
  (salt).

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6-1

• A solution may be made of any combinations of
  gases, solids, and liquids.
• A colloid is a mixture with small un-dissolved
  particles that do not settle out. (Ice-Cream).
• Solutions and colloids differ in the size of
  their particles and how they affect light.
• A colloid contains particles large enough to
  scatter a beam of light.
• Solutes lower the freezing point of a solvent,
  and solutes raise the boiling point of a solvent.

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6-1

• Oil Vinegar Salt Water
• Solution Suspension
• Water Solvent
• Salt Solute

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6-2

• Concentration and Solubility

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6-2

• Solutions differ in concentrations
• A dilute solution has only a little solute
  dissolved in the solvent. (Salt in water)
• Concentrated solution has more solute dissolved
  in the solvent. (Concentrated Orange Juice
  more orange dissolved in water.)

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6-2

• To measure concentration, you compare the amount
  of solute to the amount of solvent or to the
  total amount of solution.
• Concentration by Volume
• of Volume vSolute x 100
• vTotal

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What does that mean?

• Example
• 25 mL ethanol is added to enough water to make
  100 mL of solution. Find the percent by volume
  of ethanol
• Volume of ethanol vSolute (25 mL ethanol)
  
• vTotal (100 mL solution)
• Solve 25/100 .25
• .25 x 100 25 of volume of ethanol.

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6-2

• The factors that affect the solubility of a
  substance are
• 1. Temperature
• 2. Pressure
• 3. Type of solvent
• Many solids become more soluble as the
  temperature of the solvent increases.

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6-2

• Solubility measures how well a solute can
  dissolve at a given temperature.
• Saturated holds as much dissolved solute as
  possible.
• Unsaturated does not hold as much dissolved
  solute as possible.

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6-3

• Acids are compounds that share characteristic
  properties in the kinds of reactions they
  undergo
• Characteristic Properties
• Sour
• Reacts with metals and carbonates producing
  carbon dioxide.
• Turns blue litmus paper red
• Corrosive (eats away at other materials)
• Reacts with certain metals and produces hydrogen
  gas.
• Example Hydrochloric Acid (HCl)

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6-3 Bases

• A base is a substance that has characteristic
  properties
• Tastes bitter
• Turns red litmus paper blue
• The opposite of an acid.
• Example Ammonia (NH3)

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6-4

• Acids and Bases in Solution

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6-4

• An acid is any substance that produces hydrogen
  ions (H) in water.
• Bases are made of metals combined with hydroxide
  ions (OH-) negative charge. Bases produce
  (OH-) hydroxide ions in water.
• Acids and bases may be strong or weak.
• Strong molecules react to form ions in solutions.
• Weak has fewer molecules that break up into ions.

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6-4

• Ph Scale ranges from 0-14.
• Hydrogen ions
• High
  Low
• 2 3 4 5 6 7 8 9 10 11 12 13 14
• Strong---------------weak strong-------------
  ------------weak
• acid base
• neutral

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6-4

• Example Rainfall
• Both Rainfalls are acidic which is more?
• Normal Rainfall 5.5
• Acid Rain (pollutants) 3.5
• 3.5 is a stronger acid on the Ph scale.

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6-4

• Neutral is a balance between a base and an acid.
  
• Examples of neutrals are water or salt.
• A neutralization reaction produces water and a
  salt.

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6-5

• Digestion and Ph

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6-5

• Setup egg experiment in notebook
• Topic Egg Experiment
• Materials
• Procedures
• Prediction of outcome tomorrow?

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6-5

• Food must be broken down into simpler substances
  that your body can use for raw materials and
  energy.
• Digestion includes two processes
• Mechanical digestion grinds and mashes large
  food particles into smaller ones.
• Chemical digestion breaks large molecules into
  smaller molecules.

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6-5

• Some molecules provide the body with energy and
  some are the building blocks for the compounds in
  muscle, blood, skin, and bones.

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6-5

• Chemical digestion takes place with enzymes. For
  some digestive enzymes, the Ph must be low, for
  others, the Ph must be high or neutral.
• Teeth grind the food.
• Food gets wet with saliva. Saliva has a Ph
  balance of 7.
• Food arrives in the stomach. Cells in the lining
  of the stomach release enzymes and hydrochloric
  acid Ph 2. (Pepsin)
• Food released to the small intestine surrounded
  by a fluid called bicarbonate Ph 8. This
  completes the break down of carbs, fats, and
  proteins.