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hello and welcome to organic chemistry
this is part one of an overview of chapter one in your textbook
copies of these slides that i'm talking about can be found in a separate
file it's a pdf file
and these correspond to slides I typically show in my face to face
classes
and i just want to kinda hit some highlights here and not go through all
of these individually. Most of them
i think are kinda self-explanatory in terms of what they're trying to tell you
and i just want to give an overview here
and what i don't finish in this first five minutes i will appear in a second little
miniature video
alongside this one
uh... you may find it useful to access these slides in that pdf file to have in
front of you
while i'm talking about it
and all this stuff
that is mentioned here it is in greater detail in your textbook of course
staying there certainly encouraged to read all about that
This first slide
defines what organic chemistry is. Nowadays it's just a matter of if it has
carbon it is organic
in the old days organic meant that it would come from something that
was living or had once lived from a plant or a tree or a human or an animal
and it was long thought that the only way you could get organic chemicals was
to take them from one of these living organisms
but what this slide refers to is an experiment from back in eighteen twenty-eight
in which a inorganic substance, ammonium cyanate was heated and transformed into
urea
which was
already known to be organic--it's one of the components of urine, which is where
it gets its name
and so is really just a matter of how
atoms were connected
as to whether or not they could be classified as organic
and things like urea can be made in the laboratory from scratch or it can be
isolated certainly from
living creatures as well
a lot of organic chemistry does focus on types of
compounds that are from living systems because they are a of interest to us
but on the other hand if it has carbon it's organic regardless of
its source
so that's going to
be the definition we go by
this next slide refers you to the first ten sections of chapter one
there's a lot of stuff in here that's
background that comes from general chemistry about bonding, especially covalent
bonding between adams
and say your book does a good job of reviewing that, but
it is assumed that you've got a handle on all of this material
before we move forward into
chapters two and
three and so on
this title here "structure determines properties" that really is the motto of
organic chemistry
over and over we're going to be seeing how atoms are connected in molecules and
paying attention to such things
because whether something is good for you bad for you
helpful for toxic or neither one, everything is determined by what atoms
our present and how they are interconnected
so we're going to be spending some time
just dealing with those
interconnections and talking about how we represent those on paper
so it like a lot of subjects organic chemistry has a language
of its own and symbolism that we will
want to get familiar with
these next slides talk about
the beginnings of covalent bonds. When nonmetals hook themselves to one another
another they share pairs of electrons
and some of the stuff as it says here goes back
two hundred years or more
so i'm really trying to catch you up on the last couple a hundred years
worth of
chemical science here, at least in the first
chapter two
his first chapter talks a lot about valence electrons in atoms
how
refers to the outer energy electrons and again you textbook goes into more detail
than i will here
but that's our starting point because
in any atom it's those outer electrons that are responsible for the bonds that
take place
for sodium it's not so important that
that we keep up with all eleven of its electrons. it's really that only single
electron on the energy third energy level that's important
will see a lot of oxygen as we go along and for oxygen that's those last six
electrons that matter there
and for pretty much every element we see in organic chemistry it's going to come
from one of these groups with the blue arrows
so that as it says the group number automatically gives us a handle on how
many valence electrons
a given atom
would possess
We'll talk more about this in the part two video here
stay tuned