History and Uses

• Carbon

  • the sixth most abundant element in the universe, has been known since ancient times
  • is most commonly obtained from coal deposits
• Three naturally occurring allotropes of carbon are known to exist:

  • amorphous
  • graphite
  • diamond
• Amorphous carbon - formed when a material containing carbon is burned without enough oxygen for it to burn completely.
• Black soot

  • is used to make inks, paints and rubber products.
  • also be pressed into shapes and is used to form the cores of most dry cell batteries
• graphite

  • one of the softest materials known
  • is a form of carbon that is primarily used as a lubricant
• Naturally occurring graphite occurs in two forms

  1. alpha
  2. beta
• Alpha type - all artificially produced graphite
• Coke - its used as a lubricant, graphite
• Coke - is made by heating soft coal in an oven without allowing oxygen to mix with it
• Lead - the black material used in pencils is actually carbon
• Diamond

  • the third naturally occurring form of carbon
  • hardest substance known
• white carbon

  • fourth allotrope of carbon
  • transparent material that can split a single beam of light into two beams known as birefringence
  • very little
• Buckyballs

  • Large molecules consisting only of carbon
  • has 60 or 70 carbon atoms
  • looks like a soccer ball
• Carbon-14

  • a radioactive isotope of carbon with a half-life of 5,730 years
  • is used to find the age of living things knows as radiocarbon dating
  • Used decays into nitrogen-14
• Carbon-based molecules have three fundamentals structures

  • straight chains
  • branched chains
  • rings
• three structures of carbon-based

  A) Straight chains

  B) Branched chains

  C) Rings

  
• isomers - carbon makes four bonds, it is able to exist in many different forms
• Allotropy - behavior exhibit by certain chemical elements
• allotropes - an element exists in more than one crystalline form
• Carbon is an element that exhibits allotropy