CH' 25 Acid, Bases,

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CH. 25 - Acid, Bases, Salts

• Acid - is a compound with a hydrogen ion (H).
• What are some characteristics of acids?
• Corrosive
• Taste sour
• Strong electrolytes
• pH lower than 7

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Types of Acids

• Acetic acid - vinegar
• used to pickle things
• used to clean glass
• Acetylsalicylic acid - Aspirin
• Carbonic acid - soft drinks
• Hydrochloric acid - stomach acid
• Nitric acid - used in dynamite fertilizers

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• Nitric acid also burns human skin and leaves a
  yellow stain. The yellow stain is a protein
  indicator.
• Sulfuric acid - used in car batteries and
  fertilizers.
• This is one of the strongest acids
• It is used in a lot of manufacturing

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• Sulfuric acid is a strong dehydrating agent.
  When it comes into contact with an organic
  compound it dehydrates the compound by removing
  the water molecules from the organic molecule and
  leaving carbon.

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Bases

• Base - is a substance that produces hydroxide
  ions (OH-).
• Characteristics of bases
• corrosive
• strong electrolyte
• bitter taste
• pH above 7

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• All bases have a negative ion (-)
• All acids have a positive ion ()
• The prefix OH in a formula is the symbol for an
  alcohol and has no relationship with OH-
  (hydroxide ion). Dont confuse the two.

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Types of bases

• Sodium hydroxide - lye
• drain cleaner
• used in soaps
• Calcium hydroxide - plaster mortar for filling
  cracks.
• Ammonia - NH4 or NH3
• very harmful if inhaled
• fertilizer

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• pH scale measures the concentration of hydronium
  ions in a solution (H or H3O).
• Stronger acids have more H3O ions
• Stronger bases have more OH- ions.

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• Acid rain is precipitation with a pH lower than
  5.6.
• What is neutralization?
• A chemical reaction between an acid and a base.
  The acid and base neutralize themselves by
  producing H2O.

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• What is a salt?
• A compound formed when the negative ions from an
  acid combines with the positive ions from a base.
  They neutralize the charges.
• Most salts are composed of a metal and nonmetal

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• A titration is a process used to find out the
  concentration of an acid or base by neutralizing
  them.
• This is done by adding so much acid to a base
  until it neutralizes.

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• An indicator of phenolphthalein turns a base a
  pinkish color when added to a base.
• The base will then turn a clear color when it
  becomes neutral by adding an acid solution to the
  base.
• The point at which the base clears up with a drop
  of acid is the endpoint.

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• Soaps are organic salts
• They are formed by combining fats or oils with
  sodium hydroxide or potassium hydroxide.
• Saponification is the process of making soap.
• Soap ionizes when combined with water to form a
  cleaning agent.

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• Using NaOH to form a soap, forms a solid soap.
• Using KOH to form a soap, forms a liquid soap.
• Detergents are also organic salts much like
  soaps.
• An ester is an organic compound formed when an
  organic acid reacts with an alcohol.

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• Esters are used as additives for candy and
  gelatin. It gives flavors for apple, banana, and
  strawberry for candies.
• Synthetic fibers (polyesters) are formed much
  like an ester, but with a COOH and OH group added.