Physical Properties of Organic Compounds

   PROPERTIES                     Alkanes                                    Alkenes                                             Arenes                            Halogen Derivatives
     TYPES                Aliphatic     Aromatic                     Aliphatic     Aromatic                     Benzene                    Arenes             Haloalkanes     Haloarenes
                                                                                                                                                      CH3                                              Cl

     EXAMPLE            H3C        CH3                             H2C         CH2                                                                                 CH3Cl

                           CnH2n+2               CnH2n                  CnH2n                                     C6H6
 NOMENCLATURE                                                      Presence of cis             CnH2n–2                                     Variable              CnH2n+1X                 C6H5X
                             ~e                 Cyclo~e           and trans isomer                               Phenyl~
                                                                                                                                                              Higher bp than
                                                                                                                                                              corr. alkanes due
                                                                  es with  C
                                                                                                                   80°C                                       to larger Mr.
                       es with  C
                                                                  Similar bp as                                                                               (for some also
                                         –                                                                    Higher bp than
                        in Mr = More e                           alkane with same                                                                            due to presence
                                                                                                              6C alkane (69°C)
                       = more id-id                               number of C                                                                                 of pd-pd)            Comparable bp
                       *Branching  bp
                                               Higher bp          *bp may be
                                                                                           Higher bp          and 6C alkene                              –
                                                                                                              (63.5°C).             Dependent on e                                  to corr. alkyl
                                               than corr.                                  than corr.
  BOILING POINT        Branched isomer                            slightly higher for                                                  cloud size             Bp es              halides i.e higher
                       has lower surface        aliphatic         cis isomers as            aliphatic         Comparable bp                                   -with size of X.
                       area than                                  the dipole                                                       (molecular weight)                               bp than corr.
                                                alkanes                                     alkenes           with cyclohexane                                Effect of id-id
                       straight-chain                             moment do not                                                                                                        alkanes
                                                                                                              (81°) and                                       forces outweigh 
                       isomer = lower                             cancel out = pd-
                                                                                                              cyclohexene                                     polarity of bond
                       id-id interactions.                        pd interactions 
                                                                                                              (83°C).                                         i.e weaker pd-pd
                                                                  Higher bp
                                                                                                                                                              -with more subsn
                                                                                                                                                              of X
                       es with  C
                                                                                                                   5.5°C             Dependent on
                       M.P affected by                                                                                              molecular weight
                                                                                                              Higher mp than
                       how close the
                       molecules can                              es with  C
                                                                                 g                            6C alkane (–            and shape.                                  Comparable mp
                       pack together           Higher mp          Trans–isomers
                                                                                           Higher mp          95°C) and 6C                                    Higher mp
                                                                                                              alkene (–138°C).                                                      to corr. akyl
                        Branchg may           than corr.         pack better into a       than corr.                              For isomers, 1,4-          than corr.
  MELTING POINT                                                                                               Comparable mp        usually has the highest                        halides i.e higher
                                mp              aliphatic         regular lattice i.e.      aliphatic         with cyclohexane                                alkanes due
                          Though less                             higher bp than                                                   mp compared to 1,2-                              bp than corr.
                                                alkanes                                     alkenes           (6.5°).                                         to larger Mr.
                          efficient id-id                         cis-isomers.                                                     and 1,3-. More                                      alkanes
                                                                                                              Has higher mp        symmetrical molecular
                         forces, isomer
                                                                                                              than cyclohexene     fits better into crystal
                        able to pack into                                                                     (–104°C)
                         regular arrays                                                                                            lattice.
    SOLUBILITY                       Insoluble                                   Insoluble                                   Insoluble                                        Insoluble
  (POLAR SOLVENTS)                                                                                                                                               (unable to form H bondg with water)
    SOLUBILITY                     Soluble (CCl4)                                    Soluble                                     Soluble                                      Soluble
(NON POLAR SOLVENTS)                                                                                                       (acts as solvent)
     DENSITY                                  Less Dense                                  Less Dense
                        Less Dense              (Denser than       Less Dense               (Denser than       Less Dense              Less Dense                             Denser
   (WRT WATER)                               aliphatic alkanes)                          aliphatic alkenes)

                                                                 Physical Properties of Organic Compounds

   PROPERTIES                Hydroxy Compounds                                Carbonyl Compounds                 Carboxylic Acid & Derivatives                  Nitrogen Compounds
     TYPES                Alcohols       Phenols                            Aldehydes     Ketones                Carboxylic A. A. Derivatives                 Amines            Amides
                                                                   OH       H                  R                                                                                 O
                                                                                                                                                            R   N     R
     EXAMPLE               CH3OH                                                C     O            C      O         RCOOH                                                R       C      N      R
                                                                                                                                     H3C       C       Cl
                                                                            R                  R                                      ethanoyl chloride
                         CnH2n+1OH                                                                                                                            ~amine/     1°: ~oic acid ~amide
 NOMENCLATURE                                          C6H5OH               ~al/formyl~        ~one/oxo~            ~oic acid          ~yl chloride                       2°: alkyl on N as sub.
                          CnH2n+2O                                                                                                                            amino~
                        Much higher
                            than                                                                                                     Acid chlorides:
                                   g                                                                             Higher bp due to
                         correspon                                                                                                     Lower bp wrt to       Polar compds
                                                                                                                   H bonding in
                       alkanes.IMF H                                       Polar compds. Higher bp than                                 carboxylic acid       (ex 3°) can H
                                                                                                                  polar compd.
                                                                                                                                        because of its       Bondg. Higher       High bp due to H
                           bond .                   182°C                   non-polar compds of similar                                                                                g
                                                                                                                                      inability to form H     mp than non-        bond , usually
                                                  Higher than                           Mr.                        Stronger than
  BOILING POINT                                                                                                  alcohol because -
                                                                                                                                           bonding.         polar compds of      higher than corr
                       Lower alc are           hexanol (156.5°C)                                                                                              similar Mr but
                       liquids at room                                                                              OH is more                                                   carboxylic acids.
                                                                            Lower bp than acid and alc.                               Acid amides:           lower than alc
                       temp till 12C                                                                                 polarized
                                                                                                                                                             and carboxylic         (1° or 2°)
                                                                              because no H bonding                (presence of e–     Has –NH2 group
                                                                                                                                      and posses IM H             acid.
                       *Length of Alkyl                                                                          carbonyl groups)
                                                                                                                                     bonding. Higher bp.
                       Chain (id-id)

                                                                                                                                                            Higher mp than
                                                                           Polar compds. Higher mp than non-                         Acid chlorides:           non-polar
                        Much higher                                            polar compds of similar Mr.                                         g                             High mp due to H
                                                     41°C                                                        Higher mp due to    Polar, no H B             compds of               g
                           than                                               Lower mp than acid and alc.                                                                          bond , usually
  MELTING POINT                   g               Higher than                     because no H bonding
                                                                                                                   H bonding in                              similar Mr but
                        correspon                                                                                  polar compd.                             lower than alc        higher than corr
                                                hexanol (–52°C)                                                                       Acid amides:
                         alkanes.                                                                                                                g          and carboxylic       carboxylic acids.
                                                                           Branching & packing affects mp too.                         Polar, H B                acid.

                                                 Partially soluble in rt        Lower aldehydes and
                         Lower alc are                                                                            Lower acids          Acid derivat.s:
                                               due to H bg but has big                                                                                       Lower amines
    SOLUBILITY         soluble. Solubility                                 ketones are soluble in water,                              depend on size                               Lower amides are
                        as C  due to 
                                               h.phobic ring. Solubility                                         are soluble in        Amides & Acid
                                                                                                                                                            are soluble due
                                                                                                                                                                                 soluble due to H Bondg
  (POLAR SOLVENTS)                             is enhanced by heating      ability to form H bonding with                                                     to H Bondg
                        h.phobic nature                                                                              water            Chloride: soluble
                                                 or addition of alkali.                  water
    SOLUBILITY                                                        Soluble (solubility decreases with increasing C for all these compounds)
      DENSITY                                Similar                                    Similar                                 Similar                                        Similar
     (WRT WATER)


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