Preparation and Properties of SOAP

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Preparation and Properties of SOAP
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What is soap?

• Soap is the sodium or potassium salt of a
  long-chain fatty acid.
• Ex. Sodium Stearate
• CH3CH2(CH2)14CH2CO2-Na
• ---Non-polar----------------------Polar

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How does soap work?

• Because like dissolves like the nonpolar end of
  the soap molecule can dissolve the greasy dirt,
  and the polar or ionic end of the molecule is
  attracted to water molecules.

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Emulsion

• An emulsifying agent is a substance used to
  disperse one liquid in the form of finely
  suspended particles or droplets in another
  liquid. This is what soap is

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How is soap formed?

• When we treat fats or oils with strong bases such
  as lye (NaOH) or potash (KOH) they undergo
  hydrolysis and form glycerol and soap.

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Properties of soap

• Because soaps are salts of strong bases and weak
  acids, they should be weakly basic. However,
  sometimes soap can be basic enough to cause skin
  damage so an alkalinity test must be performed on
  our soap after we make it today.

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More properties of soap

• Soap becomes ineffective in hard water. Hard
  water contains large amounts of Ca2 and Mg2
  salts. Because of this, synthetic detergents
  have become common alternatives for soap.

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And some more properties

• In acidic solution, soap is converted to free
  fatty acid and therefore loses its cleansing
  action.
• C17H35COO-Na H ? C17H35COOH Na

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Today we will

• Use vegetable oil to make soap.
• Use alcohol as a solvent and NaOH to hydrolyze
  the fatty acid into our soap compound.
• Filter our soap

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We will also

• Test the properties of soap
• Emulsifying properties -we will mix oil and water
  and see how the addition of our soap effects the
  mixtures ability to form an emulsion.
• Hard Water Reactions - we will test our soap with
  minerals associated with hard water to
  demonstrate their effects on our soap.
• Alkalinity - we will test the basicity of our
  soap.

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Caution!

• Alcohol is FLAMMABLE! Do not allow near an open
  flame or heat source.
• Do not take your soap home for personal use!!

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Safety Concerns Calcium Chloride Dihydrate

• Inhalation irritant, coughing and shortness of
  breath
• Ingestion irritation of the mucous membranes,
  gastrointestinal upset, vomiting and abdominal
  pain
• Skin contact irritant, burns
• Eye contact mechanical abrasion of the eyes and
  burns
• Mutagen and tumorigen

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Safety Concerns Denatured Ethanol

• Inhalation coughing, shortness of breath,
  drowsiness and loss of appetite
• Ingestion headaches, gastritis, intoxication,
  blindness and death
• Skin contact cracking, flaking and defatting of
  the skin
• Eye contact pain and blurred vision
• Tumorigen, mutagen, teratogen and reproductive
  effector

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Safety Concerns Ferric Chloride

• Inhalation irritant
• Ingestion irritation of the mouth, throat and
  digestive tract, low blood pressure, tachycardia,
  skin discoloration and coma
• Skin contact irritant and can be absorbed
  through the skin
• Eye contact tearing and burns
• Reproductive effector

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Safety Concerns Magnesium Chloride

• Inhalation irritation of the mucous membranes
• Ingestion abdominal pain, vomiting, diarrhea,
  central nervous system depression, lack of
  reflexes and hypocalcemia
• Skin contact irritant
• Eye contact mechanical irritation
• Mutagen

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Safety Concerns Mineral Oil

• Inhalation irritant, coughing, shortness of
  breath and aspiration pneumonia
• Ingestion diarrhea, nausea and vomiting
• Skin contact irritant, dermatitis
• Eye contact irritant
• Tumorigen

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Safety Concerns Sodium chloride

• Inhalation irritant
• Ingestion irritant, nausea and vomiting,
  rigidity and convulsions, coma, dehydration and
  organ congestion
• Skin contact irritant
• Eye contact irritant
• Teratogen, mutagen and reproductive effector

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Safety Concerns Sodium Hydroxide

• Inhalation coughing, burns, breathing
  difficulty, chemical pneumonitis, pulmonary edema
  and coma
• Ingestion perforation, pain, nausea, vomiting,
  diarrhea, and shock
• Skin contact burns, ulcers, rash, and cyanosis
  of the skin
• Eye contact burns, conjunctivitis, and corneal
  damage
• Mutagen

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Safety Concerns Vegetable Oil

• Inhalation no known effects
• Ingestion no known effects
• Skin contact no known effects
• Eye contact no known effects