5 STRUCTURE & SHAPE OF ORGANIC MOLECULES Flashcards
what exerts greater repulsive force? lone or bonding pairs?
lone pairs exert greater repulsive force
what are functional groups?
atom/group of atoms that have a specific structure/sequence. these groups convey certain physical/chemical properties for a molecule
what are hydrocarbons?
compounds containing only carbon and hydrogen
what are alkanes?
contains a single c bond. c-c
what are alkenes?
contains a double c bond. c=c
what are alkynes?
contains a triple c bond.
what are aromatic compounds?
ring with double/single c bonds.
what are alkyl/aryl halides?
halogen connected to alkane/aromatic compound
what are alcohol?
hydroxl group (OH) connected to carbon, etc. single bond w carbon
what ether?
oxygen and element connected to carbon, etc. single bond w carbon
what are amines?
nitrogen connected to carbon,etc. single bond w carbon
what are aldehydes?
oxygen double bonded to carbon. hydrogen bonded to same carbon
what are ketones?
oxygen double bonded to carbon.
what are carboxylic acids?
oxygen double bonded to carbon. hydroxyl connected to the same carbon.
what are esters?
oxygen double bonded to carbon. another oxygen single bonded to same carbon.
what are amides?
oxygen double bonded to carbon. nitrogen single bonded to same carbon
why are specific wavelengths of light absorbed by molecules?
because energy levels are quantized
what does IR absorption correspond to?
bond vibrations (specific molecular motions). IR energy is absorbed when frequency of light matches the “normal” frequency of vibrations for that bond
molecular bonds can be thought of as…?
balls and springs that vibrate as a harmonic oscillator
what is k in regard to the harmonic oscillator?
force constant that is proportional to strength (“stiffness” of the bond)
what is μ in regard to the harmonic oscillator.
is the reduced mass. a value that compensates for the two different masses in the bond (harmonic oscillator)
in the harmonic oscillator, what does a large k indicate?
a tighter spring aka STRONGER BOND! also larger k=higher energy vibrations