PRPM112: ALKANES

• alkanes


  Saturated hydrocarbons with the general formula CnH2n+2
• saturated


  only C-C and C-H single bonds and contain the maximum possible number of hydrogens per carbon
• CnH2n+2


  general formula of alkanes
• straight-chain alkanes, or normal (n) alkanes,


  carbons are connected in a row,
• branched-chain alkanes


  compounds with branched carbon chains
• alkyl group


  partial structure that remains if a hydrogen atom is removed from an alkane
• natural gas and petroleum deposits


  major sources of alkanes
• natural gas


  consists chiefly of methane but also contains ethane, propane, and butane
• petroleum


  a complex mixture of hydrocarbons that must be separated into fractions and then further refined before it can be used.
• petroleum


  fractional distillation
• molecular weight increases


  Properties of Alkanes:

  
  

  increases both boiling point and melting point as ____________
• branching


  Properties of Alkanes:

  
  

  it lowers alkane's boiling point
• fractional distillation


  separates crude mixtures based on differences in boiling point
• paraffins

  "parum affinis"


  alkanes are referred to a word derived from latin meaning slight affinity
• oxygen, chlorine, etc


  alkanes react under appropriate conditions with __________
• rxn of alkanes in combustion


  reaction of an alkane with O2 occurs in an engine or furnace when the alkane is used as a fuel.
• fuel


  using this in combustion, the reaction of an alkane with O2 occurs in an engine or furnace
• alkane + oxygen


  CH4 + 2O2 → CO2 + 2H2O + 890 kJ (213 kcal)

  
  

  the reactant
• carbon dioxide, water, and heat


  CH4 + 2O2 → CO2 + 2H2O + 890 kJ (213 kcal)
• rxn of alkanes in halogenation: Cl2


  when a mixture of the two is irradiated with ultraviolet light (denoted hv)
• rxn of alkane with Cl2


  sequential replacement
• ultraviolet light


  denoted hv