Activity #06-Extraction

• Extraction


  Transference of compound(s) from a solid or liquid into a different solvent or phase
• Common method of extraction

  • Shaking the solution or suspension of the organic compound with a solvent in which the compound is soluble and which is immiscible with the liquid containing the compound
• The law concerns the quantitative partitioning of a substance between two immiscible solvents at a given temperature
• A substance will distribute or divide itself between the two solvents so that the ratio of the concentration in one solvent to the concentration in the second solvent is constant
• 1% aqueous solution of adipic acid


  Hexenedioic Acid (CH2)4(COOH)2, crystalline powder with practically no odor, Acidulant in baking powders, Melting point is 121-154°C, Boiling point is 265°C, pH 2.5 to 3.0, Main use is in the production of 6,6 nylon, also used in resins, plasticizers, lubricants, polyurethanes, and food additives, Characterized as stable, nonhygroscopic, and slightly soluble, with a water solubility of 1.9 g/100 ml at 20°C
• Benzoic acid


  Colorless monoclinic crystalline solid, Melting point is 122.4°C and sublimes readily at 100°C, Boiling point is 249°C, slightly soluble in water, Used as topical antifungal medication and insect repellant, preservative to prevent growth of microbes to keep food safe, Not safely given to babies because it may cause jaundice, no specific antidote, only treat the symptoms
• Crystal violet


  Blue, aniline-derived dye with antifungal and antimitotic properties, Dark green powder or greenish, glistening pieces with metallic luster, Melting point is 215°C, Very soluble in water
• Phenolphthalein


  White or yellowish-white minute, triclinic crystals, often twinned, Odorless, Melting point is 262.5°C, Insoluble in benzene and petroleum ether, slightly soluble in carbon disulfide, soluble in ethyl ether chloroform, and toluene, very soluble in ethanol, acetone, and pyrene, Used as cathartic or laxative, indicators and Reagents
• 1. amyl alcohol


  Colorless liquid, Density is 0.8247 g/mL, Boiling point is 131.6°C, slightly soluble in water and easily soluble in organic solvents, strong smell and sharp burning taste, Pure is non-toxic, impure is toxic, Used as Food additives and flavoring agents, anti-freezing agent
• Sodium hydroxide


  Colorless liquid that is more dense than water, appears to be solid white, corrosive to metals and tissue, Basic solvent, White or nearly white pellets, flakes, sticks, fused masses or other forms, Solutions are clear or slightly turbid, colourless or slightly coloured, strongly caustic and hygroscopic and when exposed to the air they absorb carbon dioxide, forming sodium carbonate, Boiling point is 1388°C, melting point is 323°C, easily soluble in cold water and freely soluble in ethanol
• Sodium chloride


  White crystalline solid, taste is salty, Boiling point is 800.7°C, soluble in water, Intravenous solution is indicated for use in adults and pediatric patients as a source of electrolytes and water for hydration, Also, designed for use as a diluent and delivery system for intermittent intravenous administration of compatible drug additives, Food spice and flavorant
• Ether


  Clear colorless liquid with an anesthetic (sweetish) odor, less dense than water and slightly soluble in water, Boiling point is 94.3°C, Melting point is -116ºC, Used as a solvent to make other chemicals
• Salting-out effect


  1. Add a drop of 0.1% aqueous solution of crystal violet to 5 ml of distilled water in two separate test tubes

  2. Add 1 ml of n-amyl alcohol

  3. Shake the mixture well until the colors in the water layers of both solutions are of the same intensity

  4. Dissolve enough salt to make the aqueous layer saturated in one of the mixtures

  5. Compare the time it takes for the two layers to separate in the two test tubes

  6. Compare the colors of the aqueous layers in the two test tubes
• Determination of efficiency of extraction

  1. Prepare 250 ml of 0.05 M solution of NaOH from a 1M solution of NaOH

  2. Get 35 ml of 1% aqueous solution of an organic acid from the instructor and place it in a dry beaker

  3. Measure exactly 10 ml of the acid solution into an Erlenmeyer flask and titrate this with the 0.05M NaOH using a drop of phenolphthalein indicator, record the volume of NaOH used

  4. Pipette another 10 ml of the acid solution into a separatory funnel or tube and extract it with 10 ml of solvent, drain the lower aqueous layer into a flask, pour the upper layer from the top of the funnel into a bottle labeled "ETHER EXTRACT"

  5. Titrate the aqueous layer with 0.05M NaOH, record the volume of NaOH used

  6. Pipette another 10 ml of the acid solution into a separatory funnel, extract the solution twice with 5 ml of the solvent each time, separate the aqueous layer, and titrate it with the 0.05M NaOH, record the volume of the acid left after the two extractions

  7. Tabulate the results