Explanation of Organic Chemistry terms.

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Explanation of Organic Chemistry terms.

Postby chikis on July 18th, 2014, 4:27 am 

A homologous series is a family of organic compound which follows a regular structrura patterng, in which each successive member differs in its molecular formula by a .
My question is, what do the before and after mean?
Last edited by chikis on July 18th, 2014, 5:34 am, edited 1 time in total.
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Re: Explanation of Organic Chemistry terms.

Postby Natural ChemE on July 18th, 2014, 5:15 am 


-CH2- is a methylene bridge. The two lines on either end symbolize bonds, though what's at the end of those bonds is left unspecified. If we used a more algebra-like notation, -CH2- could be written as -CH2-. A simple example of something with a methlyene bridge would be propane (CH3-CH2-CH3).

The quoted text in the OP refers to something like the series of simple, linear alkanes:
  1. CH4 (methane)
  2. CH3-CH3 (ethane)
  3. CH3-CH2-CH3 (propane)
  4. CH3-CH2-CH2-CH3 (butane)
  5. CH3-CH2-CH2-CH2-CH3 (pentane)
  6. CH3-CH2-CH2-CH2-CH2-CH3 (hexane)
  7. CH3-CH2-CH2-CH2-CH2-CH2-CH2-CH3 (heptane)
  8. etc.
The pattern being that they're all the same thing, except varying by the number of methylene bridges. Even methane's just H-CH2-H.
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Re: Explanation of Organic Chemistry terms.

Postby redwhitechem on June 10th, 2016, 6:06 am 

CH2 Methylene is the simplest of organic compounds which contain carbon double bonds.
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Re: Explanation of Organic Chemistry terms.

Postby peterle on December 1st, 2017, 9:36 am 

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Re: Explanation of Organic Chemistry terms.

Postby BioWizard on December 1st, 2017, 9:51 am 

peterle please don’t spam our forums :]
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