The Stories of two chemicals:

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The Stories of two chemicals

CFCs
OZONE
Activity 1
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At the end of this activity you must be able to
answer questions related to the stories of two
chemicals (Lesson 1.1 p. 3 to 5)

• Take a paper from the box. The number you take is
  your table
• 2. Each group needs a leader, a reader, a writer
  and a drawer. If there are more than 4 students
  in the group, there can be more readers, writers
  and drawers.
• 3. The leader must make sure that everybody pays
  attention, guide the discussions after each
  paragraph, and organize de work. He/she must also
  take the time so each task can be completed.

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E-molecule-150.jpg
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Cont. Activity the stories of two chemicals
4. Each student must complete the given activity
paper 5. The readers must read out loud pages 3
to 5 stopping to discuss and complete the paper
after each paragraph 6. The writers must write
definitions and important ideas in the poster 7.
The drawers must draw the required figures and
diagrams in the poster.

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Cont. Activity the stories of two chemicals
8. The group must find out one important idea to
share with the whole class and find a creative
way to present it including it in the poster (for
example a rhyme, an object that represents the
idea, a song, a joke, an abstract drawing, etc.)
9. One person from the group will share the
given important idea in a creative way 10. The
poster and presentation will be graded 11. The
activity paper completed must be signed by the
teacher to get the credit

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This is how you will be evaluated

• Group work
• Participation in your group
  10 points
• Finish on time 10 points
• Final poster
• Neat and attractive
  10 points
• All definitions complete 10
  points
• Drawings and diagrams
  10 points
• Important idea creatively presented
  10 points
• Presentation
• Presents the important idea clearly 10
  points
• 4. Auto-evaluation 30 points

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Ways of gaining knowledge
Social Sciences
Philosophy
Art
Religion

Literature
Others
Science
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Science
Life Science
Physical Science

Environmental Science
Physics
Chemistry
Matter, energy, and their relation.
Matter, its composition, and its changes.
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Chemistry
is the study of
matter, its composition, and the changes it
undergoes.
You and all the objects around you are composed
of matter. By studying matter and the way it
changes, you will gain and understanding of your
body and all the stuff you see and interact
within your everyday life. Chemistry, matter and
change, Glencoe, 2002

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Chemistry tries to answer 4 basic questions
What is this matter that I have?.
How much (of this matter) do I have?
How can I change it (matter)?
How much (matter) can I get and how fast?
Chemists observe and measure properties of matter
and the way matter changes to answer these
questions.
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you have the power
By understanding what matter is, how much
you have of what kinds, how it can be changed
from one form to another, and how fast those
changes occur, you have the power to leave
the World better than you found it.
The alternative is to remain ignorant of matter,
to allow changes to occur without considering
their effect on your life, or to allow
others to decide what changes will be made in the
matter that makes up your world and that of
future generations.Herron, J.D.et al,Chemistry,
D.C. Heath and Co.,Lexington, Ma, 1993,p. 4 and 5
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Matter is anything that has mass and occupies
space.
Mass is the amount of material. Mass is what
gives an object the properties of weight and
inertia.
Weight is a force and is due to the pull of
gravity on the object.
Energy The ability to cause changes in matter
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Branches of Chemistry



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The Scientific Method

• A scientific method
• is a systematic approach used in scientific
  study
• is an organized process to do research
• provides a method to for scientists to verify
  the work of others
• We can describe some steps of this scientific
  approach, but it is important to realize that
  each scientist may not follow them exactly or in
  a specific order. Therefore they must describe
  the exact procedure followed.
• The validity of the results must be confirmed by
  other scientists, following the described
  procedure.

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The Scientific Method Some Definitions
What do you observe in this diagram?
Observations
-- a group of dark dots -- dots of different
sizes -- dots of different shapes -- a white
background -- more concentration of dots in some
areas
-- it may be a Dalmatian -- sniffing the
ground -- or drinking water -- many leaves on the
ground -- or many rocks
Inferences
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The Scientific Method Some Definitions
Observation What you perceive with your senses,
qualitative data, or using tools (measurements),
quantitative data. Inference An interpretation
of an observation. Examples Classify the
following as observations or inferences It is
very cloudy It is going to rain The boy is
sad The boy is crying The student is looking
at an open book The student is reading
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The Scientific Method Some Definitions
Background Information Before starting your
investigation on a topic you like, you must find
what is already known about the topic. You
observe and infer first. Then you research in
books, encyclopedia, magazines, your computer,
talking to experts, etc The summary of this
knowledge is your background information and must
be the base that supports your hypothesis. Hypoth
esis Temporary or tentative explanation of what
has been observed. Things as they might be. An
educated guess. Experiment A set of controlled
observations that test the hypothesis.
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cont. the Scientific Method Some Definitions
Variable A quantity or condition that can have
more than one value. Independent Variable The
variable that you plan to change (manipulated
variable). Dependent Variable The variable that
changes in response to a change in the
independent variable (responding
variable). Control a standard for comparison.
It may be an extra set up or just a color to
compare etc. Controlled variables Variables
that you control so they dont affect the results.
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cont The Scientific Method More definitions
Conclusion A judgment based on the the
information obtained Theory An attempt to
explain why something happens. It is an
explanation that has been supported by many
experiments. Law Summarizes what happens. The
formulation of an observed behavior. It is a
relationship in nature that has been supported by
many experiments. Model A representation. A
theory in the form of a picture or idea about
something that cannot be viewed directly . It can
also be defined as a visual, verbal and/or
mathematical explanation of experimental data.
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Scientific Method diagrams
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Types of Scientific Investigations
Pure Research seeks to gain knowledge for the
sake of knowledge itself. Applied Research Is
research undertaken to solve a specific
problem. Give me some examples of pure and
applied research. Some great discoveries have
been made by accident, unexpectedly.
Technology Is the practical use of scientific
information, which is concerned with making
improvements in human life and the world around
us.
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Safety Rules By following safety rules in the
lab, you will help keep both yourself and others
safe.

• Be prepared for the lab procedure. Read the
  ____________ prior to class or work. Do not
  proceed unless you understand the instructions.
• Do not perform experiments without your
  ____________s permission. Never work __________
  in the laboratory.
• Maintain a lab space ____________of paper, texts,
  and other clutter. Only lab manuals and notebooks
  should be in the work area.
• Read all _________ carefully before using a
  chemical. Check the name twice. If you are not
  familiar with the chemical, read the material
  ____________ data sheet first.

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• Use _________ the chemicals assigned to your
  area. Do not borrow chemicals from other labs or
  use items not listed on your labs inventory.
• Be familiar with the locations and procedures of
  all ___________ equipment, including safety
  _________, fire __________, fire
  __________________, spill controls, eyewash
  station, and fire exits.
• Follow ______written and verbal instructions. Do
  not attempt experiments beyond those that have
  been approved by your instructor or supervisor.
  Ask for ________________ if a technique or
  procedure is unclear or too difficult.
• Do not ________ or __________chemicals.

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• If chemicals come in contact with your eyes or
  skin flush the area immediately with large
  quantities of _____________. Immediately inform
  your _______________ of the nature of the spill.
• Wear splash goggles, face shields, gloves, and an
  approved apron in the laboratory. The gloves
  should match the chemicals being used for the
  procedure. Lab coats may be required in some
  labs.
• Wear appropriate clothing. Shoes must be ________
  toed. Coats (weather) are not permitted. Bulky or
  expensive clothing and jewelry should not be
  worn. Leg coverings are a must.
• Long hair should be ___________ or ________ back.

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• Do not wear contact _____________in the lab, even
  under goggles. Lenses can absorb vapors and are
  _____________ to remove in case of an emergency.
• Do not ______, ________, or __________ gum in the
  lab.
• Do not use _______________ liquids near ignition
  sources such as burners or hot plates. Never
  leave a Bunsen burner ____________.
• When heating a substance in a test tube, be
  careful not to ____________ the mouth of the test
  tube at another person or yourself. Never look
  down the mouth of a test tube.
• Do not heat graduated cylinders, burettes or
  pipettes with a laboratory ________________.

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• Do not use chipped, broken, or cracked
  _________________ in any procedures.
• Return unused chemicals to the ________________
  container. Make sure all containers are labeled
  and that the labels are readable.
• Do not insert droppers into ______________
  bottles. Pour a small amount of the chemical into
  a ____________. Follow the proper ____________
  for the disposal of chemicals, broken glass and
  products of reactions. Do not pour down the
  ____________ sink without checking the
  procedures.
• Know the correct procedure to ____________ acid
  solutions. Always add the acid slowly to the
  ____________. Do not add water to the acid.

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• ____________ all chemical spills and accidents to
  your instructor or supervisor immediately. Refer
  to the spill procedures posted for the lab.
• Keep the balance area clean and never place
  chemicals ____________ on the ____________ of the
  balance.
• ____________ the area after you have completed
  your work. Use only cleaning products approved
  for the work area.
• ____________the personal protective equipment
  used and your ____________ before leaving the
  lab.
• Make sure the gas and water are turned ______.
  Wash your hands with soap and water before you
  ____________the lab.