The title of this course, Cchemistry in
the Earth System really gets at the way
that we're trying to highlight the
synergy between the differences sciences
here
We want the Earth science phenomenon to
motivate students and give the chemistry
content more real world relevance. At
the same time, understanding the
chemistry is going to give students a
deeper insight into the processes that
are shaping the Earth and its going to
equip them to overcome some of the
environmental problems facing our planet.
The conceptual flow you see here from
the framework is one way to accomplish
these goals. Remember the Framework
is just an example -- districts, science
departments, and teachers can choose any
course sequence they want -- adopting this
conceptual flow exactly or starting
completely from scratch.
Let me show you what we were thinking
when we designed this course sequence.
We chose combustion as a unifying theme
because it illustrates so many chemical
principles and has really profound
implications for the earth system we
start off with a brief instructional
segment that focuses on observing
combustion at the macro scale students
practice observing and describing the
both properties of matter and changes to
it
they also might notice those gases given
off including the co2 that's going to be
one of the threads that ties together
many of the topics throughout the course
in order for students to explain all the
different things that are going on
during this phenomena of combustion
they really need to be developing their
model the nature of matter and that
model should start on pretty simply
thinking just about interacting
particles and that lays the foundation
for thermodynamics for reaction kinetics
and the ideal gas law allow them to
really understand the nature of
properties like density and processes
like heat transport these heat transport
processes really come alive when you're
looking at the earth system as they
control everything from global climate
to plate tectonics the students explore
the evidence for the motion of massive
blocks of the Earth's crust
they begin to ask questions but what's
causing that motion
ultimately realizing that it's all
driven by heat transfer from Earth hot
interior to the cooler service in high
school students are now extending their
model of matter that goes beyond simple
particle
they're ready to look at the internal
structure of the atom and explore the
patterns in the periodic table that
result from that structure these
patterns allow students to predict how
atoms will interact and bond together in
chemical reactions in the instructional
segment of chemical reactions students
focus on explaining macroscopic
behaviour using models at the atomic
scale
they use their model the internal
structure of the atom to explain how
chemical bonds and intermolecular
attractions are all driven by electrical
attraction this model allows students to
explain chemical potential energy
measured at the macroscopic scale in
terms of changes of electrostatic
potentials as Adams change bonding
partners
students can revisit the combustion
reaction in particular
so they can explain how fossil fuels are
an energy resource for society and also
noting that co2 is a product
this sets up an in-depth exploration of
the chemistry of climate change
here students treat the earth is a
thermodynamic system and they develop a
model verse energy balance explain the
role that co2 place is a greenhouse gas
that absorbs energy and infrared do the
specifics of its chemical bonds but the
discussion goes beyond chemistry
noting the impact of climate change on
earth systems including the interactions
with human society then students return
to the topic of chemical reactions from
the perspective of chemical engineers
they're looking at how to manipulate
chemical systems to adjust the rates and
products of chemical reactions one way
to introduce these topics is through a
chemical system involving carbon dioxide
and nurse atmosphere and its ocean the
ocean has become forty percent more
acidic since humans began burning fossil
fuels is our primary energy source
this has massive implications for marine
life
it's not just the tropical coral reefs
that are affected either
many of the creatures at the base of the
food chain here in coastal california
are already being stressed students
investigate the chemistry of carbonic
acid and how it affects more in life
they tie these changes to human activity
and design solutions
they're going to help minimize these
human impacts so as we step back and
look at the course as a whole
you can see that common thread of
combustion really ties together the
chemistry and the earth science and how
the earth science phenomena are really
have the potential to engage students
and relate the chemistry two important
issues that are going on in the world
around us
