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					                 Administrative Procedures Rates of Reaction Inquiry - FPC


                    Portland Public Schools Common Science Assignment
                          HS Foundations of Physics and Chemistry
                         Rates of chemical reactions
                          Administrative Procedures
Using the equipment and chemicals provided by your teacher, design, conduct and analyze the results of an
              experiment that investigates factors that affect the rates of chemical reactions.


Description:

In this inquiry students will explore how some reactions occur faster than others. Using
the concepts of temperature or particle size, students will create an experiment that will
investigate the relationship between one of these factors and the rate of reaction. The
teaching sequence introduces and provides demonstrations of reaction rates; measuring,
calculating and predicting individually and through group work.


The task assesses students' understanding of scientific inquiry including the following
skills: observation, background research, scientific procedures (including investigation
design, measurement techniques, and error analysis), data collection, data display,
scientific questions, formulating a hypothesis.

This task is designed to take students approximately 6 to 9 hours; the amount done in
class will vary among teachers depending on student needs.

Scoring:

Scoring will done in the same way as Oregon State Scientific Inquiry Work Sample
Scoring. You score each section in the scoring guide (Forming a Question or Hypothesis,
Designing an Investigation, Collecting and Presenting Data, Analyzing and Interpreting
Results) on the 1-6 scale. All four scores will be reported for the Common Assignment.
Scores are due to Research and Evaluation by January 13, 2009.

Overall Task Content Area:

        Foundations of Physics and Chemistry

Specific Knowledge Areas:

        Oregon State Standards: SC.CM.PS.02.04 ( Describe the factors that affect the
rate of chemical reactions)

        PPS Standards: SCI.HS.PC.MTR.2.4
               Administrative Procedures Rates of Reaction Inquiry - FPC


Performance Expectations:

      conducting investigations
      using equipment
      gathering, organizing, and representing data
      formulating conclusions from investigational data
      writing to communicate scientific inquiry design, interpretation and analysis of
       data



General Instructions to the Teacher:

This task, including the writing process for the final report, is designed to take students
approximately 6-8 hours or seven-nine 50 minute classes

Students will be working individually on the final draft of this exercise. Collaboration
during the design of the experiment and data collection is acceptable and encouraged as
part of the scientific process. Teachers may model and guide various aspects of the
inquiry process as needed or appropriate

Students should be ready to work as soon as periods begin. A central supply area, if
needed, should be easily accessible. All supplies should be clearly labeled and their use
monitored by the teacher.

If teachers plan to use the product of the activity for the Oregon State Science Work
Sample, please adhere to the guidelines for Science Work Sample collection.
Information can be found on the PPS Science Website:
http://inside.curriculum.pps.k12.or.us/.docs/pg/12323

Materials for “Temperature or Particle Size”:

          15 x 150 mm test tube                             Stopwatch
          Test tube rack                                    Thermometer
          Ice                                               Clear glasses or test tubes
          Water (cold, hot, room temp)                      Alka-Seltzer tablets
          Alka seltzer tablets                              Mortar and pestle
          Goggles                                           Stopwatch
          Glove
               Administrative Procedures Rates of Reaction Inquiry - FPC


Preparation:

       Background Knowledge: essential questions

              How do you know that a chemical reaction has occurred?
              Compare and contrast a physical change versus chemical change.
              What are the steps for the scientific method?
              If energy is added or removed from a system, how does that affect the
               particle movement and collisions?



Sequence of teaching – pre-inquiry

The goal of this section is to expose students to the necessary concepts and experiences
so that they can be properly equipped to embark on a guided inquiry activity by the end
of this section. This section involves a variety of strategies including small group
cooperative learning, observation of discrepant events, and textbook reading supported by
literacy strategies.

       Warm Up question: What would affect the speed of a reaction? How?

              Have them answer this individually in their notebooks. (5-7 minutes)
              Have each student in their table groups (groups of 4) share their answers.
               (5 minutes)
              After they share, the group comes up with one answer to share out with
               the class (recorder/reporter)

       Demonstrations

               Particle Size
                   Powdered Zinc v. Mossy Zinc in Hydrochloric Acid

                      1. In an Erlenmeyer flask place the mossy zinc in and pour
                      hydrochloric acid (3-4 Molar) into the flask. Immediately place a
                      balloon over the top of the flask to capture the Hydrogen Gas.
                      Swirl the flask. Have students pay special attention to the rate at
                      which the balloon inflates.

                      2. (OPTIONAL) Before attempting this, be sure to follow all
                      safety precautions including having students at least 3 meters
                      away. When the reaction has stopped tie off the balloon, tape it to
                      the end of the meter stick. Turn off lights, light a candle. Holding
                      the meter stick from the opposite end, place the balloon over the
                      flame. BOOM!
       Administrative Procedures Rates of Reaction Inquiry - FPC


               3. Repeat step 1 but this time use powdered zinc. Have them
               compare the speed with which the balloon inflates this time.

       Temperature
       Glow sticks in ice water/hot water

          Have two beakers of water one with ice and one with hot water. Turn
           off lights. Break the glow sticks at the same time and place each one
           in a beaker.
          Have them make observations about the brightness of the glow sticks.
           Then have them predict the rate of the reaction and how temperature
           will affect how fast it goes. Then have them make final observations.



Textbook Reading & Anticipation Guide

At the end of this document is an Anticipation guide which may be used in
conjunction with section 7.4 of the textbook. The teaching sequence is as
follows:

1. Hand out the anticipation guide. If students have a journal for your class, it is
useful to have them glue or tape it in.

2. Have students read each statement and make a guess if it is true or false. This
should be done independently and fairly quickly. They should record their guess
in the Me column.

3. If time permits, take a class poll by reading each statement aloud and asking
which students believe the statement is true or false. Record what the majority
thinks in a visible location.

4. Instruct the students to open their books to the section and to find evidence if
each statement is true or false. If you have a method of note-taking like Cornell
Notes, you can instruct them to follow that format. Students should be
encouraged to look for evidence and then take notes about it on the right page of
the journal. At a minimum, insist that they rewrite each statement so that it is
true. To model your expectations, you may want to do the first one together.

5. Once students have completed or at the next class period, revisit each
statement and as a class record whether each statement is true or false according
to the text.
               Administrative Procedures Rates of Reaction Inquiry - FPC


Their Inquiry:

Note: for this section teachers are highly encouraged to have students use the Inquiry
work sample template located on the OTL website at
http://inside.otl.pps.k12.or.us/.docs/pg/12323

Now they have experienced some discrepant events that involve rates of reaction. They
have had group conversations about it. They have also done some reading in the
textbook on the topic. As a teacher you can now provide the framing for their inquiry.
Offer up these following claims and ask each group to choose one of them to investigate:

Claims
1. The temperature of water affects how quickly an Alka-seltzer tablet reacts.
2. The size of the particles affect how quickly an Alka-seltzer tablet reacts. .

Once they have chosen their claim, the students must come up with their experimental
design. Following the inquiry template, they must identify their manipulated variable,
responding variable, and constants or controlled variables. They must also formulate
their hypothesis that they will use to explore this.

Available supplies
Teachers should be sure students are aware of the following resources:

1. Water at varying temperatures (room temperature, ice bath, water near boiling point
on a hot plate). Use thermometers to check the temperatures. You may use styrofoam to
maintain the temperature of the warm water.

2. Alka seltzer tablets of varying size (whole tablet, ¼ tablets, powdered tablets)

3. Test tubes (5-6 per group)

4. Scoopula

5. Stopwatch

Note: the above list is suggested as a starting point. Teachers are free to offer other
options based on ideas generated in the classroom.

Scaffolding during the data collection
If teachers are having students perform this as an inquiry work sample, they must follow
the guidelines provided by the state regarding what assistance can be provided to
students. Some potential pitfalls to warn students about and help their thinking are
provided below:

      How many trials are needed to get enough evidence to evaluate your hypothesis?
       Students sometimes perform the experiment once and conclude it is sufficient.
               Administrative Procedures Rates of Reaction Inquiry - FPC


      How will you determine which reaction is faster? Two possibilities: time the
       reaction until the tablet completely disappears or let the reaction go for a set
       time and then estimate how much of the tablet is left
      Where will you record your observations and data? Again, we recommend
       providing students a hard copy of the inquiry template from the OTL website



Scaffolding the write up
The amount of scaffolding required during this phase may vary. Provided below are
some suggestions to guide your thinking.

      Students benefit from seeing a finished product that models what is expected. If
       you have strong work samples on different topics from previous years, showing
       students a copy of it and having them score it using the scoring guide can be
       helpful.
      Students benefit from a writing process that includes the creation of a rough draft
       that is followed by some sort of self edit or peer edit activity.
      A specific peer edit activity is provided at the end of this document. Instructions
       are provided below.

   Peer Editing Activity
   This activity works best if you have at least a few students turn in a rough draft the
   day before this activity is to be done. This gives you time to photocopy a few rough
   drafts so that every student (even those who don’t bring one) will have at least one
   paper to review.

   The activity works best if each student has at least 3 different highlighter colors to
   use. Modeling with a fictitious paper or excerpt that you make up can be very helpful
   as well.

   As a teacher, you choose the foci for students to concentrate on each time they read
   the paper. Examples are provided below:

          Highlight any evidence that supports or does not support the hypothesis.
          Highlight any references to the manipulated variable in one color, the
           responding variable in a different color, constants in a third color.
           Highlight any background information that helps the reader clearly
           understand the nature of the investigation and the importance of it.
          Highlight any numbers that suggest a relationship or any out of the ordinary
           data.

After students have completed these focused readings, then show them how what they
have highlighted (or not) can help them write constructive feedback. For example, if
your first focus was highlighting in blue for evidence that links results to the hypothesis,
               Administrative Procedures Rates of Reaction Inquiry - FPC


and there is no blue on the paper, then there is a deficiency in that student’s paper that
you want them to address so that their paper is improved.

It is important to emphasize that everyone’s paper has strong points and could use
improvement. The activity is structured so that every paper receives at least some
positives and criticisms. As a teacher, you can set a minimum of how many of each.
               Administrative Procedures Rates of Reaction Inquiry - FPC


Anticipation Guide – Reaction Rates
Foundations of Physics & Chemistry

1. Find 2 pages in your journal that are blank. Tape this onto the left side page.
2. Read each statement and guess if you think if it is True or False. Record your guess
   in the Me column.
3. Turn to section 7.4 of your book (pages 212-215). Find evidence within those pages
   to determine if each of these statements is true or false. Take notes on the right side
   of your journal. At a minimum, rewrite the statement so that it is a true statement.
4. In the column marked Text, indicate whether the statement is True or False according
   to the text.

True or       Statement
False
Me Text
              1. A reaction rate is the rate at which the products change into the
              reactants over time.

              2. Reaction rates tell you how fast reactants are being used up, how fast
              the products are being made, or how fast energy is taken in or given off.

              3. Stirring is the only factor that affects reaction rates.

              4. As temperature of a substance goes up, the particles move slower.
              This causes the number of collisions to go down.

              5. As surface area goes up, the more exposure reactants have to each other.
              This allows for more collisions which makes reaction rate increase.
              6.   Stirring makes reaction rates go down.

              7. Concentration is the number of particles in a given volume.

              8. The more particles in a given volume, the fewer opportunities for
              collisions. This makes the reaction rate go down.

              9. Catalysts make a reaction slow down without being used up in the
              reaction.
               Administrative Procedures Rates of Reaction Inquiry - FPC


Peer Editing Activity
The purpose of this activity is for every person to read two lab reports other than their
own. The goal is for you to give and receive constructive feedback from classmates in
order to improve your rough drafts. Read below.

Part 1: Focused Highlighting
In this part you will be looking through the lab report with a specific focus each time.
Follow these instructions:

1. Write the first focus provided by your teacher in Focus #1.
2. Choose 1 highlighter color and mark the highlighter side with it.
3. Read the rough draft. When you come upon writing about that focus area, you will
use the highlighter color you designated to highlight that writing.

Focus #1                                                                   Highlighter 1


Focus #2                                                                   Highlighter 2


Focus #3                                                                   Highlighter 3



Part 2: Being a helpful reader
You are trying to help your classmate improve their writing so that they can get a good
grade on their final draft. Giving little feedback or saying general things like “looks
good” will not help them improve. Be specific and detailed. Look at the different
things you focused on with your highlighters. This should give you a strong sense of
what you can say in terms of feedback. See the boxes below for guidance.

Helpful Things to Say                           Things Not To Say
“I liked how you ___________ at the start       “Looks good”
of the ______ paragraph…”
“I got confused when you were talking           “I didn’t get any of it”
about _____ in the ___ paragraph. Do you
mean to say ___________”
“How does your example of ________ in           “I don’t know”
paragraph ________ relate back to your
main idea?

“Your last sentence in paragraph _____ is       “It sounds okay.”
hard to follow. You might want to think
about ________”
               Administrative Procedures Rates of Reaction Inquiry - FPC


Author of Essay: ______________________________

Name of Person Providing Feedback: ______________________

Positives. Things that were strong or you liked about the writing (at least ____).




Constructive Criticisms. Things the author might want to work on to improve their
writing (at least ___).