PORG LAB

• Hybrid orbitals


  Developed by Linus Pauling to explain the structures of molecules in space by combining atomic orbitals (s,p,d,f) into new hybrid orbitals (s, sp, sp2, sp3)
• Atomic orbital


  Expected region of electron density around an atom based on a solution to the Schrodinger wave function
• Hybridization


  The combining of solutions to the Schrodinger wave function for atomic orbitals to produce hybrid orbitals
• Hybrid orbital

  An orbital created by the combination of atomic orbitals in the same atom
• Elements and their valence bond needed

  • Carbon: 4
  • Nitrogen: 3
  • Oxygen: 2
  • F, Cl, Br, I: 1
  • Hydrogen: 1
• Steric number


  Total number of sigma bonds and lone pairs indicating the number of electron pairs (bonding and non-bonding) that are repelling each other
• Hybrid orbitals, groups attached, hybridization

  • 1: s, sp
  • 2: sp
  • 3: sp2
  • 4: sp3
• Linear sp hybrids

  • The two hybrid orbitals formed by the mixture of one s and one p orbital
• Trigonal sp2 hybrids

  • The three hybrid orbitals formed by the mixture of one s and two p orbitals
• Tetrahedral sp3 hybrids

  • The four hybrid orbitals formed by the mixture of one s and three p orbitals
• SP hybridized atom has two regions of electron density
• SP2 hybridized atom has three regions of electron density
• SP3 hybridized atom has four regions of electron density
• Distillation


  Separation process for a mixture of liquids or oils involving conversion of liquid to vapor, condensing the vapor, and collecting the distillate in another container
• Different distillation process - Simple distillation


  Refers to the "simple" separation of a solid and a liquid by evaporating the liquid and collecting it after it passes through a condenser to be changed into a liquid state
• Apparatus for simple distillation

  • Heat source, Still pot, Still head, Thermometer, Condenser, Cooling water in, Cooling water out, Distillate/receiving flask, Vacuum/gas inlet, Still receiver, Heat control, Stirrer speed control, Stirrer/heat plate, Heating (Oil/sand) bath, Stirrer
• Procedure for distillation

  Assemble the setup (simple and fractional) 2. Put boiling stones into distilling flask and introduce the liquid 3. Heat until boiling starts 4. Record temperature at first drop of distillate 5. Stop collecting at about 100 degrees Celsius 6. Measure volume of distillate and residue
• Types of distillation

  • Heat source
  • Still pot
  • Still head
  • Thermometer
  • Condenser
  • Cooling water in
  • Cooling water out
  • Distillate/receiving flask
  • Vacuum/gas inlet
  • Still receiver
  • Heat control
  • Stirrer speed control
  • Stirrer/heat plate
  • Heating (Oil/sand) bath
  • Stirrer bar/anti-bumping granules
  • Cooling bath
• Fractional distillation is a process that separates more than one substance at a time, used when boiling points are close together or mixtures are complex
• Fractional distillation is more complex due to the need for a longer still process and separate condensing apparatus, but can be operated continuously
• Vacuum distillation is used for applications like medicines and cosmetics where substance purity is very important
• Vacuum distillation may be used with either simple or fractional types of distillation but requires careful control because vacuums tend to lower boiling points
• Rotary Evaporator is used in Vacuum Distillation
• Alcoholic distillation separates alcohol from water in a water/alcohol solution by heating and condensing the alcohol-rich vapors released
• Types of alcoholic beverages

  • BRANDY - Fruit juice - 40-50% alcohol content
  • WHISKY - Cereal grains - 40-55% alcohol content
  • RUM - Molasses/sugarcane - 40-55% alcohol content
  • WINES - Grapes/other fruits - 10-22% alcohol content
  • BEER - Cereals - 4-8% alcohol content
• Raoult's Law applies to solutions when two different volatile liquids are mixed together into a solution
• Dalton's Law Formula states that the total pressure exerted by the mixture of gases is the sum of all the partial pressure of the individual gases
• Extraction involves the separation of constituents of plant or animal tissues by using a selective solvent in a standard extraction procedure
• Maceration involves placing solid ingredients in a stoppered container with the whole of the solvent and allowing it to stand for at least 3 days with frequent agitation
• Percolation involves extracting active ingredients from a macerated drug mass in a narrow cone-shaped vessel through the passage of an extracting liquid called menstruum
• Digestion is a form of maceration where gentle heat is used during the extraction process
• Infusion produces a dilute solution
• Extraction


  Maceration with gentle heat using a liquid called MENSTRUUM
• Infusion

  Produces a dilute solution of the readily soluble constituents of crude drugs for a short period of time using either cold or boiling water
• Decoction

  Extracts water-soluble and heat-stable constituents from crude drugs by boiling in water for 15 mins, cooling, straining, and passing sufficient cold water through the drug to produce the required volume
• Proper storage for plant extract

  • Container: amber-colored bottle
  • Stored in cold temperature between 0 - 5°C
  • At room temperature, treat the extract with chloroform or toluene to prevent fungal growth
• Heat fusion


  The amount of heat necessary to change one gram of a solid into a liquid at its melting point
• Official melting point of the sample

  • Aspirin: 135°C
  • Ibuprofen: 75°C
  • Acetaminophen: 168-172°C
  • Diclofenac: 284°C
• Heat added during the process of melting


  Does not bring about a change in temperature until all the solid has disappeared since the heat is converted to potential energy of the molecules which have escaped from the solid to liquid state
• Technique of mixed melting point

  Based on the fact that unlike compounds will mutually act as impurities and cause a depression in the melting point