Please put all of the metal fillings back into the

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					          General Chemistry
                        Unit 1




                   Early chemists describe
                       the first dirt molecule

 What is chemistry?
 Elements to Know
 Chemistry Careers
 Scientific Method
 Observation Lab
 Lab Safety
 Lab Equipment
 Alchemy Lab




                                                 1
At the conclusion of this unit, the student will be able to:
1.   Identify and describe the development 6 branches of chemistry out of alchemy.
2.   Distinguish between pure research, applied research, and technology.
3.   Use the scientific method to solve various problems.
4.   Use appropriate safety/lab equipment and procedures in the science classroom



We are looking for:
1. Ability to distinguish and identify various scenarios as organic, physical, biochem., analytical,
   inorganic, theoretical chemistry.



2a. Pure research is learning for the sake of knowing.
2b. Applied research is using the knowledge gained from pure research to solve a specific problem.
2c. Technology is using the knowledge gained from pure research to improve the quality of life.


3a. Identify a problem.
3b. Create a hypothesis.
3c. Identify the independent and dependent variables, and control.
3d. Write a procedure.
3e. Collect and analyze data/observations and distinguish between qualitative and quantitative
observations.
3f. Formulate a conclusion.



4a. Identify the safety features of the room.
4b. Correctly light and adjust a Bunsen burner.
4c. Identify incorrect behavior in a lab scenario.
4d. Identify names and uses for lab equipment.
4e. Demonstration of safety procedures in the lab.




                                                                                                       2
                   How Chemistry Began
    Throughout    history    people   have   tried   to   alter   their
environment to improve their way of life.       Such “tinkering” has
often lead to unexpected results.



4000 B.C.          Mesopotamian Cultures
                       Irrigation


2000 B.C.          Egyptians
                       Metallurgy and Embalming


400 B.C.           Greeks
                       Understanding of Matter


600 A.D.           India
                       Steel


1000 A.D.          Chinese
                       Gunpowder


    This “tinkering” has fulfilled two needs:
               To understand the world around them.
               To improve and protect our lives.




                                                                      3
            4
Chemistry
                                           Research
Research is done for different reasons. The type of research pursued is dependent uon what
information is important/needed.




Basic or Pure Research:
         The main goal of this type of research is to gain new knowledge about a chemical or
          process, just for the sake of knowledge.

         Chance discoveries can result from basic research.

         “I wonder what would happen if …”




Applied Research:
    The main goal of this type of research is to solve a specific problem.

    Example: CFC’s (chloro fluor carbons) in refrigerants destroyed the ozone so chemists
     formulate new refrigerants.




Technological Development:
    This type of research involves the making and use of products that improve the quality of life.

    Development can result from basic research.

Example: Teflon coating.




                                                                                                       5
Ag   Li
Al   Mg
Ar   Mn
As   Mo
Au   N
B    Na
Ba   Ne
Be   Ni
Br   O
C    P
Ca   Pb
Cd   Pt
Ce   Ra
Cl   Rb
Co   Rn
Cr   S
Cs   Sb
Cu   Sc
F    Se
Fe   Si
Fr   Sn
Ga   Sr
Ge   Ti
H    U
He   V
Hg   W
I    Xe
K    Zn
Kr
          6
7
8
Career Report
Directions: Read the handout given to you about a career in chemistry and answer the following questions. You should
use this information to write a job advertisement as a blog on my website.

    You must post your job advertisement to the blog by the end the day on ___________!
    You will respond to 3 jobs starting on _______________ You have until 3:00 on __________________ to
       respond to 3 jobs. See the blog for further instructions!




   1. Name of chemical career



   2. How much education/training do you need to qualify for this job?




   3. How much money can I make doing this job?




   4. Who is best suited for this job?




   5. What is a typical day like working this job like?




                                                                                                                       9
10
                                         Scientific Method

1.   Define the problem
         You can’t solve a problem until you know exactly what the problem is

2.   Collect background information
         What do I know and what will I need to know about the problem?

3.   Formulate a hypothesis
        A possible solution to the problem – simple is better usually!

4.   Test the hypothesis
        Perform an experiment to see if your hypothesis works.

5.   Data Analysis
       Collect data and make good observations about what is happening.

6.   Draw conclusions
       Evaluate what was found and let everyone who is interested know what you found.

     If it worked – GREAT!
     If it didn’t work – start again!!




                                  Terms of the Scientific Method

Observation –
   Statement of fact
   Obtained by using one of the five senses
   Qualitative (words) / Quantitative (numbers)


Inference –
    Attempts to make one think
    Is in the form of a question


Hypothesis –
   An explanation that can be tested
   A prediction based on observations
   Must state the conditions (variables) and explains why a phenomenon is occurring.
   Can be an educated guess.




                                                                                          11
Law -
       Set of related observations of nature.
       Generalizes a body of observations.
       Proven to be true in each and every case.
       Governs a simple or single action.
       Observation that will lead to the use of the scientific method to explain why the observation occurred.
       Many times expressed with mathematical equations.


   Example: When a gas is heated, it will expand.



Theory –
    Explanation of why a set of related observations occurs.
    Based on proven hypotheses
    Verified by multiple groups of researchers
    Tries to explain a whole series of related phenomena
    Proven within reasonable doubt
    More complex than a law

   Example: The kinetic molecular theory is used to explain why a gas will expand when heated.



                                   Law (Simple Relationship)
                                  
   Inference  Hypothesis
                                  
                                      Theory (Complex)



Testing the Hypothesis-
       Research Models limit the number of variables to two

               o   Independent Variable – The condition that is to be studied. It will be changed in the
                   experiment. It is controlled by the experimenter – "I control it".


               o   Dependent Variable – It will be affected by the independent variable. It cannot be
                   controlled by the experimenter; think results of the experiment.


           Control Group-The group that is represented in a normal situation; does not receive the
            experimental treatment.

           Experimental Group(s)-The group that receives the experimental treatment, the independent
            variable.

           Constants- all the other conditions that must remain the same (constant) for both groups.

                                                                                                              12
                             Writing If / Then Hypothesis Statements

The “IF” part of the statement:
            Mention Independent and dependent variables

Link: are related, depend on each other, can be
      correlated

The “THEN” part of the statement:
          Make an educated guess how they are related or what will happen in the experiment


If Variable 1 and Variable 2 are related then
state the relationship you believe exists between the two variables.




Example: If plant growth and amount of water are related, then the plant will grow taller the more it is watered.

Independent variable = water
Dependent variable = plant growth




                                                                                                               13
14
                                         Chemistry Lab Experience
                                             "Scientific Method"
                                                 Observation


                                  Organic Chemistry Worksheet




Reactions are a big part of organic chemistry.



You are going to witness a chemical reaction between goldenrod paper and a baking soda /water mixture.




On a ½ sheet of goldenrod paper, using a cotton swap, make a name tag for yourself.   Be creative.


Make 5 "good" observations about what is happening on the paper.



   1. –




   2. –




   3. –




   4. –




   5. –




                                                                                                         15
                                 Inorganic Chemistry Worksheet


Inorganic Chemistry is the study of _____________________________________




   1. Measure out 1 gram of each of the following metals:
      (To use the balance, put a marked tray on the balance and hit “Tare”. The value shown on the
      balance should be “0.” Add metal pieces until the value shows 1.0).

              Magnesium (Mg)
              Copper (Cu) turnings (strands)
              Iron (Fe)


       Draw the different metals:




                 Mg (Magnesium)                    Cu (Copper)                         Fe (Iron)



           A. Write observations about the different metals.

       ___________________________________________________________________________________
       ___________________________________________________________________________________
       __________________________________________________________________________

           B. Based on the amount of sample you see in each dish, rank the amount of each metal
       from “most“ to “least.”



       ________                                 ________                            ________

       (Visibly looks most)                                                         (Visibly looks least)




*Please put all of the metal fillings back into the respective dishes. Thank You!


                                                                                                            16
   2. Determine if each of the following compounds are organic or inorganic: put a check in
   the appropriate column.


                   Compound                        Organic                      Inorganic

                      NaCl

                    Cu(NO3)2

                      C2H6

                      CoBr3

                    C22H44O2

                    C12H20N5

                      CrO4




                                        Research Worksheet


1. List the types of research that take place in industry. What type of problems and information can be
obtained from each of these different types of research?



       A.




       B.




       C.



                                                                                                          17
   2.    Observations are remarks about a given sample or situation. They must be clear (create a good
         mental image) and should not reflect any personal preferences.


               Example: The air smelled good. (Bad observation – what is “good” to one person may not be
               “good” to another.

               A better observation would be:

                      The air smelled like a field of daisies.



Make 8 “good” observations about what is in the jar: not about the jar itself (continues on back)



        A.



        B.



        C.



        D.



        E.



        F.



        G.



        H.




Was this hard or easy to do? _________________
Why?_____________________________________________________________________________________
_________________________________________

                                                                                                         18
3. Without opening the white box – make 8 “good” observations about the materials in the box.



      A.



      B.



      C.



      D.



      E.



      F.



      G.



      H.




Was this hard or easy to do? _________________
Why?_____________________________________________________________________________________
_________________________________________




                                                                                            19
20
                                       Safety Contract for General Chemistry

The National Science Teachers Association urges that students be required to review and sign a contract that defines
acceptable behavior in a school science setting.


The purpose of this contract is to make the student aware of his/her responsibility for
laboratory safety.

Students should realize the implications of improper laboratory behavior. Courts have ruled that students can be just as
guilty of negligence as teachers in laboratory accidents. These guidelines are to keep you and your classmates safe.

I will:
     1.   Follow all instructions given by the teacher.
     2.   Protect eyes, face, hands, and body when involved in science experiments.
     3.   Carry out good housekeeping practices.
     4.   Know where to get help fast.
     5.   Know the location of the first aid, eye wash, fire extinguisher and fire blanket.
     6.   Conduct myself in a responsible manner at all times.

I, _________________________, have read and agree to follow the safety regulations set forth above and below on this
contract. I will closely follow the oral and written instructions provided by the teacher and/or school administration.

Date: ______________               Student Signature: ____________________________

Date: ______________               Parent Signature: ____________________________



                                                Laboratory Safety Rules
    1. Wear proper eye protection at all times during laboratory activity. Let instructor know if you wear contact
        lenses. Know the location of the eye wash equipment.
    2. Confine or tie hair that reaches the shoulders – hair is flammable!
    3. DO NOT eat, drink or chew gum in the laboratory. Never taste anything unless specifically instructed to do so by
        the teacher. No chemicals are ever to be taken from the laboratory.
    4. Never engage in horseplay or practical jokes.
    5. Footwear should cover the whole foot.
    6. Avoid inhaling chemical fumes. All chemicals are dangerous unless they are known to be otherwise.
    7. The teacher is to be notified immediately in case of an accident, no matter how trivial it may appear.
    8. Know the locations of the fire extinguisher, fire blanket, eye wash, safety shower, first aid kit and clinic.
    9. Notify instructor immediately of any spills on your clothing.
    10. Dispose of items as instructed by the teacher. Only certain chemicals can be put down the drain safely.
    11. Never return chemicals to their original container, unless told to do so.
    12. Never point the open end of a test tube being heated at anyone, including yourself.
    13. Always add acid to water (AA). This is particularly true of concentrated sulfuric acid.




                                                                                                                       21
22
23
24
25
26
27
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Name ___________________________________               Class Period__________




                                         Safety Scenarios

The diagram below and the diagram on the back, show students performing laboratory activities. Study each
diagram and write in the spaces all of the proper and improper lab techniques you can pick out. Be prepared
to discuss your answers.



                                                Picture 1




Proper Techniques                                 Improper Techniques

1.                                                        1.

2.                                                        2.

3.                                                        3.

4.                                                        4..

5.                                                        5.

6.                                                        6.




                                                                                                          29
                    Picture 2




Proper Techniques    Improper Techniques

1.                         1.

2.                         2.

3.                         3.

4.                         4.

5.                         5.

6.                         6.




                                           30
                           Lab Safety Stories


On a separate sheet of paper, list of all the safety violations for each story.




            Story #1 – there are at least 10 violations in this story.


                        Mike was the first to arrive at the laboratory. He had just
              come from playing basketball and still had on his gym shorts and
      sandals. Wanting to finish early, he began to work on the assigned lab.


Mike had not read the lab so he quickly skimmed the directions. He needed some
water to prepare a solution. There was an unlabeled bottle of clear liquid on the
bench, so he tasted it to see if it was water. It was bitter and burned his mouth.
He spit the liquid out and dumped the bottle into the sink. After preparing his
solution, he got out his lunch and began to eat while getting the balance out of the
cupboard. When he put the balance on the lab bench, he knocked over the beaker
containing the solution and it fell onto the floor and broke. He pushed the broken
pieces under the bench and got another breaker out of the supply cabinet.


He got bored so he took 2 bottles of chemicals off the teacher’s desk and put
several drops of each chemical into a beaker. He used his finger to stir the
mixture. He discarded the liquid in his beaker down the sink and then returned
the beaker to his lab drawer.




                                                                                     31
Story #2 – there are at least 6 violations in this story.


Kate decided to do the experiment right away. She put her
books, lunch and purse on one side of the lab bench so she
could work on the other half. The lab called for her to heat some water. She
turned on the gas at the gas outlet, got the Bunsen burner out of the cabinet
and lit it. To keep the clutter down, she threw the match into the garbage. She
was wearing a loose, long sleeved sweater. She reached over the flame to get a
bottle of chemical that she needed from the other side of the lab bench. Her
sleeve caught on fire. She screamed for help. When no one responded, she ran
out of the classroom with her sleeve ablaze.




                                                                                32
                       Lighting a Bunsen Burner
1. Attach the burner hose to the gas outlet at the wall.

2. Close the air and gas valves on the burner. (Turn them clockwise as
   you look at them)

3. Light a match and open the gas outlet at the wall/table.

4. Open the gas valve on the
   burner until you hear a faint
   hissing sound of gas escaping.

5. Light the burner using
   matches or a lighter.

6. Adjust the air valve until you
                                                                    Air Valve
   have a good inner cone and
   an outer cone about 5 cm
   high.

7. Close the gas outlet (at the
   Wall/table) to extinguish the flame.
                                                                         Gas Valve
   A Bunsen burner is not a
   candle. NEVER blow it out.




                         Gas Outlet




      The gas valve adjusts the height of the flame
      The air valve changes the color (temperature) of the flame

                                                                                 33
34
                                            Alchemy Lab
  I.     Problem: Can I change a penny into gold?
  II.    Hypothesis: If alchemists are associated with turning metals into gold, then when I turn a penny to
         gold, I am an alchemist!
  III.   Experiment:
         a. Materials:
                     Bunsen burner                2 metal rings                 ring stand
                     150 mL beaker                graduated cylinder            spatula
                     250 mL beaker                safety glasses                steel wool
                     5 pennies (pre 1982)         stirring rod                  wire gauze
                     zinc (granulated)            crucible tongs
                     3.0 M sodium hydroxide (NaOH)

         b. Procedure:
            1. Set up a double ring stand to heat a 150 mL beaker. Make sure the beaker is steady on the
               ring stand/wire gauze and the second ring is around the middle of the beaker. The bottom
               ring/wire gauze should be about 5 cm above the Bunsen burner.

            2. Using steel wool, buff your pennies. Keep one penny as a control for later comparisions.

            3. Place a spatula tip full of zinc into the beaker.

            4. Carefully pour 25.0 mL of 3.0 M sodium hydroxide (NaOH) into the same 150 mL beaker.
               Put the beaker on the ring stand.

            5. Light the Bunsen burner. Using a blue flame, adjust the flame so the tip just touches the
               wire gauze. Bring the solution to “near” boiling. Lower the flame to maintain the solution
               at “just under” boiling. Move the Bunsen burner out from under the beaker if needed.
                DO NOT HEAT TO DRYNESS!!
CAUTION: SODIUM HYDROXIDE IS DANGEROUS IF IT CONTACTS YOUR SKIN AND CAN CAUSE
BLINDESS IF SPLASHED INTO EYES. THE FUMES ARE IRRITATING TO THE LUNGS AND WILL
CAUSE COUGHING. THEREFORE – DO NOT BOIL – THERE SHOULD BE NO STEAM PRODUCED!

            6. Using crucible tongs, carefully add no more than four pennies to the hot solution at one
               time. Do not drop the pennies into the solution. It could cause the beaker to break or
               cause the solution to splash out. Set the third penny aside as a control to compare to the
               treated coins. Carefully stir the solution with a stirring rod. Rotate the coins in the hot
               solution by using your crucible tongs.


                                                                                                             35
         7. Carefully stir the solution with a stirring rod. Rotate the coins in the hot solution by using
            the crucible tongs.

         8. Make some observations about what is happening to the pennies in the beaker.

         9. Fill a 250 mL beaker about half full with tap water.

         10. With the crucible tongs, remove the pennies when they have completely turned to a silver
             color. Dip them into the beaker of water to rinse. Dry them in a paper towel. Set one aside
             for later comparisons.

         11. Carefully move the Bunsen burner out from under the ring stand.

         12. To turn the pennies to gold, gently heat them in the coolest part of the burner flame. Hold
             them vertically with the crucible tongs – DO NOT OVERHEAT! If the coins turn brown, you
             overheated them!

         13. After the appearance of the coin has changed, place it in the beaker of water. Then remove,
             rinse, and dry it.

         14. Record observations (in observation section) about changing the coin from silver to gold.

         15. Clean up the equipment and work area. Return equipment to the proper location.


IV.   Observations:




V.    Conclusions:




                                                                                                             36

				
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