Transcript zackipc#8 - GEOCITIES.ws

• (8) Science concepts. The student knows that changes in matter
affect everyday life. The student is expected to:
• (A) distinguish between physical and chemical changes in matter
such as oxidation, digestion, changes in states, and stages in the
rock cycle;
• (B) analyze energy changes that accompany chemical reactions
such as those occurring in heat packs, cold packs, and glow sticks
to classify them as endergonic or exergonic reactions;
• (C) investigate and identify the law of conservation of mass;
• (D) describe types of nuclear reactions such as fission and fusion
and their roles in applications such as medicine and energy
production; and
• The Rock Cycle, which was first developed in
the 18th century by James Hutton, is an
interrelated sequence of events in which rocks
are created, altered, destroyed, and reformed.
• The processes that occur below the surface of
the Earth are called Lithospheric Processes,
while processes that occur about the surface are
called Atmospheric Processes.
• Igneous rock: rock formed by solidifying magma
• Lava: magma that has reached the surface through a
volcanic eruption
• Magma: molten rock beneath the surface of the earth
• Metamorphic rock: rock formed from igneous or
sedimentary rock that has been subjected to tremendous
heat and pressure over time
• Plate tectonics: the movement of the large and small solid
"plates" on the outer skin of the earth
• Sediment: mixture of broken pieces of large rocks,
minerals, and the remains of living things
• Sedimentary rock: rock cemented together from broken
pieces of other rocks and from the remains of living things
• Weathering: the physical or chemical breaking down of
rocks
• When chemical reactions take place they are often accompanied by
heat changes
• The system (the reactants which form products) may give out heat
to the surroundings, causing them to warm up
• In this case the reactants have more stored energy than the
products. Such chemical reactions are said to be exothermic.
• The system may take heat from the surroundings, causing them to
cool down. In this case the reactants have less stored energy than
the products.
• Such chemical reactions are said to be endothermic.
• Chemical reactions happen all around us.
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When we light a match.
When we start a car.
When we eat dinner.
Even when we walk our dog.
Did you know when you put hydrogen with oxygen to
form water it is a chemical reaction.
• A chemical reaction is the pathway by which two
substances bond together.
http://web.jjay.cuny.edu/~acarpi/NSC/6-react.htm
How do light sticks work?
When the stick is flexed, a glass ampule inside
the stick breaks. This results in the mixing and
reaction of an organic oxalate (R-O-CO-CO-OR', where the Rs stand for organic groups) and
hydrogen peroxide, H2O2. The reaction that
produces a product in an 'excited' state. The
product loses energy to relax back down to its
ground state by dumping energy to a
fluorescent dye molecule present in the stick.
The dye releases the energy as brilliantly
colored light.
http://marie.frostburg.edu/chem/faq/lightstick.html
• Established in 1789 by French chemist Antoine
Lavoisier.
• States that mass is neither created nor
destroyed in any ordinary chemical reaction.
• Or more simply, the mass of substances
produced (products) by a chemical reaction is
always equal to the mass of the reacting
substances (reactants).
• To make large-scale use of the energy released in
fission, one fission event must trigger another, so that
the process spreads thoughout the nuclear fuel as in a
set of dominos. The fact that more neutrons are
produced in fission than are consumed raises the
possibility of a chain reaction. Such a reaction can be
either rapid (as in an atomic bomb)
http://library.thinkquest.org/3471/noNetscape/fission.html
• Fusion reactions are the combining of two nuclei to
form a more massive nucleus. Many fusion reactions
release large amounts of energy. An example is the
combining of two isotopes of hydrogen (tritium and
deuterium) to form helium and a neutron plus a large
amount of kinetic energy in the reaction products
• In addition to this work, ORNL conducts world-class
programs in other aspects of neutron science and
technology: producing radioisotopes vital to the
nation's nuclear medicine program, including
californium-252 for treating ovarian cancer and tin117m for easing bone cancer pain; Exploring how fast
neutrons damage materials used in fusion and fission
energy production; And refining neutron activation
analysis to detect very low concentrations of impurities
in materials. ORNL has performed pioneering work in
all these areas of R&D
http://www.ornl.gov/publications/core/nuclear.html
• Canadian Rockhound: The Rock Cycle
• http://www.conceptsandchallenges.com/3edcnc/3e
dcnc_s/earth_s/earth_rocks_s.html
• Active Chemistry: Chemistry Principles: Cool
Chemistry Show
• http://marie.frostburg.edu/chem/faq/lightstick.html
• http://library.thinkquest.org/3471/noNetscape/fissi
on.html
• http://www.ornl.gov/publications/core/nuclear.htm
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