Monday, 18 February 2013

I AM THE GOD OF HELLFIRE! AND I BRING YOU...



...an organic chemistry video that got slightly out of hand:



An introduction to organic chemistry and organic compounds - WITH FIRE!!!!

In nature on this planet, there seem to be two types of matter, which vary according to how they respond to heating.  One lot, such as sugar, alcohol, urea, vinegar and olive oil, changed

irreversibly when heated, and the other changed reversibly.  The Swedish chemist Berzelius noted

that whereas the reversible substances were from things which had never been alive - inorganic -

the irreversible ones always seemed to be from things which were either alive then or had

recently been alive - organic compounds.  Another oddity was that organic compounds could appear

to consist of exactly the same elements in the same proportions without being the same substance.

 For instance, diethyl ether and ethanol (known commonly as alcohol) have exactly the same

formula, but diethyl ether is an anaesthetic gas and ethanol is a liquid used as a recreational

drug.

All of these compounds contain carbon (although not all carbon chemistry is organic).  Carbon is

special because it can form into chains and rings, and also form double bonds.  Whereas silicon,

which is immediately below carbon in the periodic table, can also do some of this, its compounds

tend to be more unstable.

Natural philosophers (scientists) used to think that organic and inorganic chemistry were

governed by entirely different rules and had nothing to do with each other, a philosophy known as

"vitalism".  That is, life and non-life are entirely different.  However, in 1828, Friedrich

Wohler (missing umlaut) managed to synthesise urea from entirely non-living substances.  Up until

that time, it was thought that only a kidney could produce urine, so the boundaries between

inorganic and organic chemistry began to blur.  In 1845, Adolph Kolbe managed to make acetic

acid, the acid in vinegar, in a similar way, and it became clear that organic compounds, although

special, could be understood using the same principles as inorganic ones.

As can be seen from the structural formulae in this video, the explanation for the differences

between such substances as diethyl ether and ethanol is that although their molecules contain the

same atoms, the atoms are in different arrangements.

Organic compounds are organised into homologous series, which are named systematically.  The

prefixes, such as meth-, eth-, prop-, but- and then the various Greek number words, describe how

many carbons are in the molecular "skeleton", and the suffixes, such as -ane, -ene, -ol and so

forth, indicate what class of compound they are - organic acid, alcohol, various types of

hydrocarbon and so on.

The second video will cover more basic organic chemistry, including fractional distillation and

fossil fuels, as well as some more of the nomenclature.


Unfortunately, that nasty double-spacing is in the doobly-do - i blame Notepad.  I hate double-spacing.

Anyway, the purpose of this particular blog entry is to provide materials for the video, so here are the structural formulae for them:


 
(That last one is straight from Wikipedia, which is why it looks different).

Thankfully, that seems to be done now.  Tomorrow's video, which is on the Doomsday Argument, follows.  I might as well start on it now.