introduction - georgia standards frameworks/9-1… · electron configuration, orbital notation, ......

Introduction FINDING PATTERNS Unit Framework Annotation This unit, Finding Patterns, takes an inquiry approach to understanding the patterns of properties that exist among the elements. These patterns in properties are then linked to the wave-mechanics concept of atomic structure and the quantum atom. Beginning with isotopes and average atomic mass, as a way of understanding the importance of the atomic number in the identity of an element, the unit then uses the periodic table, as the ultimate graphic organizer for our knowledge of atomic structure and properties. The trends (patterns) of the periodic table are then connected to electron configuration. The skills involved in this unit include: calculating average atomic mass of isotopes; graphing and analyzing data for the trends of the periodic table; writing and analyzing electron configurations; describing periodic trends; conducting flame tests to identify elements; performing mole/mass conversions. Understanding how the body of scientific knowledge has developed through the work and insights of many scientists is central to this unit. The activities and tasks are suggested but should be adjusted, omitted or enhanced as needed for specific class situations. Some classes may need more time, practice, or instruction for some concepts. Others may need less. For these reasons, the number of days required may need adjustment.

Note on safety: Review and require students to follow all appropriate lab safety rules, including the wearing of goggles and aprons, fire safety, clothing safety and the safe handling of chemicals. Students must be thoroughly knowledgeable about the use of safety equipment including the shower, eyewash, sinks, and fire extinguisher.

Approximate Duration for the Unit Framework 3 – 4 Weeks

Standards Focus Content Standards SC2. Students will relate how the Law of Conservation of Matter is used to determine chemical composition in compounds and chemical reactions. SC2c. Apply concepts of the mole and Avogadro’s number to conceptualize and calculate mass, moles and molecules relationships. SC3. Students will use the modern atomic theory explain the characteristics of atoms. SC3b. Use the orbital configuration of neutral atoms to explain its effect on the atom’s chemical properties. SC3d. Explain the relationship of isotopes to the relative abundance of atoms of a particular element. SC3f. Relate light emission and the movement of electrons to element identification. SC4.Students will use the organization of the Periodic Table to predict properties of elements. SC4a. Use the Periodic Table to predict periodic trends including atomic radii, ionic radii, ionization energy, and electronegativity of various elements. SC4b.Compare and contrast trends in the chemical and physical properties of elements and their

Georgia Department of Education Kathy Cox, State Superintendent of Schools

GeorgiaStandards.Org

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placement on the Periodic Table. Integrated Characteristics of Science Standards SCSh1a,b,c. Students will evaluate the importance of curiosity, honesty, openness, and skepticism in science. SCSh2a,b,c. Students will use standard safety practices for all classroom laboratory and field investigations. SCSh3a,b,c,d,e,f. Students will identify and investigate problems scientifically. SCSh4.a,b. Students will use tools and instruments for observing, measuring, and manipulating scientific equipment and materials. SCSh6a,b,c,d. Students will communicate scientific investigations and information clearly. SCSh7a,b,c,d,e. Students will analyze how scientific knowledge is developed. Students will recognize that: a. The universe is a vast single system in which the basic principles are the same everywhere. b. Universal principles are discovered through observation and experimental verification. c. From time to time, major shifts occur in the scientific view of how the world works. More often, however, the changes that take place in the body of scientific knowledge are small modifications of prior knowledge. Major shifts in scientific views typically occur after the observation of a new phenomenon or an insightful interpretation of existing data by an individual or research group. d. Hypotheses often cause scientists to develop new experiments that produce additional data. e. Testing, revising, and occasionally rejecting new and old theories never ends. SCSh8. Students will understand important features of the process of scientific inquiry. Students will apply the following to inquiry learning practices: a. Scientific investigators control the conditions of their experiments in order to produce valuable data. b. Scientific researchers are expected to critically assess the quality of data including possible sources of bias in their investigations’ hypotheses, observations, data analyses, and interpretations. d. The merit of a new theory is judged by how well scientific data are explained by the new theory. e. The ultimate goal of science is to develop an understanding of the natural universe which is free of biases. f. Science disciplines and traditions differ from one another in what is studied, techniques used, and outcomes sought. Complementary Standards SC1a Relate the role of nuclear fusion in producing essentially all elements heavier than hydrogen. SC1b Identify substances based on chemical and physical properties SC3 Students will use the modern atomic theory to explain the characteristics of atoms. SC3a Discriminate between the relative size, charge, and position of protons, neutrons, and electrons in the atom. SC3c Explain the relationship of the proton number to the element’s identity.



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Understanding and Goals Unit Understandings, Themes, and Concepts Atomic theory has been built on the measurements, observations, discoveries, and interpretations of data by many scientists, and has been modified over the centuries by both major discoveries and small modifications until today our current understanding of atomic structure is best explained by the wave-mechanics model. This understanding unites the understandings of Unit One, Finding Order, with this unit, Finding Patterns, and is a unifying theme of chemistry. • The modern atomic theory provides an explanation for the many patterns found in the properties of

the elements, including atomic number, electron arrangement, reactivity, and bonding, • The periodic table, arranged by atomic number, reveals a tendency for properties to repeat in a

periodic pattern (periodicity), and can be used to predict the properties and uses of an element. • These periodic trends exist for many properties of the elements including atomic radii, ionization

energy, and electronegativity. • Although different numbers of neutrons exist in different forms (isotopes) of the same element, it is

the number of protons that determines the atom’s identity. Average atomic mass reflects the relative abundance of these isotopes.

Complementary Understandings introduced in the unit, Finding Order • Order is inherent in the structure of matter. • Matter is composed of a limited number of elements. • Elements were created through nuclear events in the universe. • All matter possesses physical and chemical properties that are related to its atomic structure. • Measurement is an important means of understanding matter. • The fundamental unit for measuring amount of substance is the mole. Essential Questions • What does electron arrangement have to do with fireworks? • How does average atomic mass reflect the relative abundance of the isotopes of an element? • How is molar mass related to atomic mass? • In what ways does the periodic table organize what we know about the elements?

o What trends in chemical and physical properties are revealed by the periodic table? • How has the periodic table been amended over the years to reflect new understandings of atomic

structure? • How are electrons arranged in energy levels, sublevels, and orbitals outside the nucleus? • How can electron arrangement be used to identify substances?

o How can flame tests be used to identify metals?



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Balanced Assessments

Method/types Informal Observations

Dialogue and Discussion

Selected Responses

Constructed Responses

Self-Assessments

Average atomic mass calculations Monitor and conference with groups on “Organizing the Elements Lab” Monitor for understanding as students graph trends Silent roundtable task Check electron configurations Tickets out the door for electron configuration, orbital notation, and Lewis dot structure

Oral questioning during Organizing Elements Lab & Periodic Trends Lab Discussion/ overview of periodic trends Identifying mystery elements (based on various properties) Check for understanding the nature of the mole (taught in Unit, Finding Order)

Items on unit test Items on electron configura-tion quiz

Organizing Elements Lab Flame test lab report Draw an atom (formative) Graph trends of the periodic table Electron configuration, orbital notation and Lewis dot structure work The Periodic Table Salesman GRASP Assessment

Check electron configuration Group coaching occurs in Organizing the Elements Lab (peer assessment)



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Unit Performance Task(s) Unit Performance Task Title Two alternatives are given here for the unit performance task. Choose one of these, or differentiate, or design your own.

Research Project on Modern Lighting ToxiTown GRASP activity

Description/Directions see Unit Appendix: These tasks are explained in the Performance Task Section, located after the Sequence Instruction and Learning Section. The tasks are also hyperlinked between these two sections of this framework. Rubric for Performance Task Not included; rubrics should be designed by the teacher and based on the elements that are being assessed.

Student Work Sample with Teacher Commentary (To be added as available)

Sequence of Instruction and Learning

Each activity is placed in context in the sequence of activities, tasks and assessments. Details and descriptions are located in the appendix of this unit.

Teacher Activities • Launch unit with brief video / multimedia

presentation showing vivid fireworks. • Discussion of the development of the periodic table, following the student inquiry task. • After silent roundtable, debrief the silent roundtable on board • After the student jigsaw activity, discuss the trends of properties on the periodic table. • Facilitate the language analysis diagrams • Instruction on electron arrangement based on the quantum theory

Student Activities • Atomic mass activities • Draw an atom task ( draw and write analysis • Create a periodic table inquiry task • Stump the teacher questions • Silent roundtable task • Element survey lab task • Mystery element task • The periodic table salesman task • Jigsaw of periodic table trends task • Three dimensional graphing of periodic trends or use of appropriate technology to graph trends



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• Discuss the production of spectra Demonstrate spectrum tubes or use a multimedia presentation on the emission spectra of elements • Zinc Pyrotechnics demonstration

• Distributed and differentiated practice on electron arrangement • Brainstorm patterns in nature • Wintergreen mint luminescence activity • Simulation of an element’s emission spectrum • Flame test lab • Cooperative test questions

Sequence of Activities, Tasks, and Assessments for Unit

Teacher Note: In the following lessons the tasks are hyperlinked to the instructions for that task and the instructions are linked back to the task. The tasks are also located at the end of this unit in the appendix and can be printed out along with the unit.

Day

1

EQ1: How do the colors in fireworks depend on electron arrangement in the atoms of their elements? SC3f, SCSh7c Understanding: Atomic theory has been built on the measurements, observations, discoveries, and interpretations of data by many scientists, and has been modified over the centuries by both major discoveries and small modifications so that our current understanding of atomic structure is best explained by the wave-mechanics model using quantum numbers. Teacher Note- This is an understanding that will be developed as this unit progresses. Today’s activating strategy is intended to create curiosity about the bright colors of fireworks and link it to atomic structure which is introduced in the unit, Finding Order. The details of electrons gaining and emitting energy will be covered in a later lesson. Activate the learning for this unit with a brief video clip of fireworks. Ask students how they think the different colors are produced. Tell students that they will be able to answer this question by the time they complete this unit. Teacher note: An internet search will produce numerous sites with video clips of fireworks. Some sites to get you started include http://chemistry.about.com/od/fireworkspyrotechnics/http://www.ci.natchitoches.la.us/Festival/Fireworks.asp, http://www.sandlingfireworks.com/index.html. EQ2: How does average atomic mass reflect the relative abundance of the isotopes of an element? SC3d Understanding: Although different numbers of neutrons exist in different forms (isotopes) of the same element, it is the number of protons that determines the atom’s identity. Average atomic mass reflects the relative abundance of these isotopes. Review basic structure of the atom (See unit: Finding Order). Student pairs carry out the Average Atomic Mass Activities.Debrief and have students calculate average atomic mass of an element. Use data on the



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http://chemistry.about.com/od/fireworkspyrotechnics/

http://www.ci.natchitoches.la.us/Festival/Fireworks.asp

http://www.sandlingfireworks.com/index.html

relative abundance of the natural isotopes of hydrogen, or another element for this activity. Summarizing strategy: Assign students two different isotopes of the same element to draw. Draw an atom activity, task. This task was first used in Unit 1, Finding Order. It is repeated here to make sure students understand how isotopes of the same element differ. Note in the instructions that it is very important that the student not only draws the isotopic forms, but also gives a written explanation of what s(he) understands about the structure. Teacher note: Introducing atomic mass at the beginning of this unit is done intentionally to give the student an understanding of the difference in atomic mass and atomic number. This will provide background for the discussion of Mendeleev’s periodic table and the modern periodic table.

Day 2

E.Q: In what ways does the periodic table organize what we know about the elements? SC4, SCSh1,7,8e Understandings: • The periodic table, arranged by atomic number, reveals a tendency for properties to

repeat in a periodic pattern (periodicity), and can be used to predict the properties and uses of an element.

• These periodic trends exist for many properties of the elements including atomic radii, ionization energy, and electronegativity.

Teacher Note; This is intended to be an inquiry task. DO NOT tell the students to arrange their table by atomic number. This is something that they will discover as they proceed with the task. Also, DO NOT allow the use of any periodic tables during the task. This lesson is devoted to a task that will lead the students to an understanding of the periodic table by simulating Mendeleev’s famous card shuffling activity. Give background on Mendeleev as a teacher trying to organize chemical information for his students. DO NOT call attention to a copy of the periodic table at this time. Cover or remove wall copies. Using collaborative groups, have students create a periodic table based on their own organization of the elements’ properties. See Create a Periodic Table for general directions. Students summarize their organization by reporting out to the class. Keep class engaged by informing them that all must be prepared, since the group reporter will be selected randomly. If time allows, encourage group members to coach each other on reporting.



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Day 3

EQ: In what ways does the periodic table organize what we know about the elements? SC4 Understanding: The periodic table, arranged by atomic number, reveals a tendency for properties to repeat in a periodic pattern (periodicity), and can be used to predict the properties and uses of an element. Activate this lesson by building on the student work from the previous lesson. Have students compare their organizations of the elements to the official periodic table, which will now become prominent in the classroom. Ask students to speculate on whether there could be other possible formats for the periodic table. Discuss history of the development of the periodic table and the major breakthroughs in understanding that support its arrangement by atomic number. (Use the technique of 10-2 for delivering the information. (Lecture, discuss, demonstrate, or show for approximately ten minutes. Then allow two minutes for collaborative partners to “think, pair, share” or allow two minutes for students to complete notes and ask questions.) Repeat with next segment of content. As a summarizing review for this lesson, a suggested activity is to show the video clip, “The Elements Forged in Stars”. This video makes the connection between the evolution of elements and their location on the Periodic table. See resource list for details. For accountability and assessment turn things around a little bit. Have students write five questions related to the content of the video. Then randomly draw a name or two depending upon time and see if the teacher can answer all the questions on those students’ lists. Take up all questions for informal assessment.

Teacher note: Use a name beaker to promote engagement. Have students write their names on popsicle sticks and keep these in a beaker. Draw sticks out of the beaker randomly to call on students. After a stick is pulled put it right back in the beaker so that it is always in the pool of names.

Days

4-5

EQ: In what ways does the periodic table organize what we know about the elements? o What trends in chemical and physical properties are revealed by the periodic table? Understandings: • The periodic table, arranged by atomic number, reveals a tendency for properties to repeat in a periodic pattern (periodicity), and can be used to predict the properties and uses of an element. • These periodic trends exist for many properties of the elements including atomic radii, ionization energy, and electronegativity. Teacher note: The activating strategy is meant to increase involvement, and interest. Knowing the names and symbols of the elements is not, in and of itself, the goal of this course. However, familiarity with names and symbols should come through usage and be embedded in the course. This activity is a one means of launching or continuing this process. Activating strategy: Once again cover the classroom periodic tables. Distribute one



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whiteboard and four different color dry erase markers to each team of four students. Instructions to students: This will be a silent roundtable task. Each student will write with a different color marker. When instructed to start, one member of the group will write the name of an element on the board, then pass it to the right. Each member of the group will add one element to the list, and pass it on to the next member. If a member cannot think of an element, that member must think for at least 10 seconds before passing the board on. Continue to do this without talking, until the group cannot think of anymore elements. Debrief: List the teams’ names across the top of a blackboard. Call on each group to offer one element. As each element is listed, other groups check it off. Each element that a team gets on the board is worth one point. Start each round with a different group, in order to give each group the advantage of going first. Groups may also challenge each other. (a common error is that a team will list an alloy or compound instead of an element.) If a challenge is correct, the challenging team gets the point. If the challenge is wrong, the team loses one point. If a team is not paying attention, and names an element that is already on the board they lose one point. Points can be used as bonus points for the team members with every student getting the total team points divided by the number of team members. (A variation on this task is to repeat it using symbols rather than the names after students have been using the symbols in the context of the course, or after being assigned specific symbols to learn.)

Element Survey Lab, Task: The teaching strategy for this lesson is exploratory/inquiry based. Students will observe the macroscopic properties of representative elements. Give each student a periodic table with large blocks and only the symbols on it. Students can remain in their teams, or in a traditional seating arrangement, or at stations. Provide numerous representative elements in closed vials. Students should locate the correct block on the periodic table for each element, then list as many physical properties as they can in the correct block. Analysis: Ask students to review the properties on their table and summarize any similarities and trends.

Students summarize this lesson by completing the Summarizing activity: Mystery element activity.

Assign the Performance assessment: The Periodic Table SalesmanThis assessment requires the student to explain the central importance of the periodic table to the understanding of chemistry. It can be assigned on this day, with the understanding that the lessons over the next few days will inform their understanding and prepare them to complete this assignment. Set due date for Day 8 or later.



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Days 6,7,8

EQ: In what ways does the periodic table organize what we know about the elements? SC4, SC2b o What trends in chemical and physical properties are revealed by the periodic table? • Understanding: Periodic trends exist for many properties of the elements including atomic radii, ionization energy, and electronegativity. Activate lesson by using the language analysis diagram task. Students would also be interested in seeing variations of the periodic table from other countries, or three dimensional versions. See three-dimensional Periodic Tables at PeriodicTable.com, Benfey's Spiral Periodic Table, and other sites listed in the resource section. Teaching strategy: Use this inquiry activity in jigsaw format, as described below: Give groups of four students data on atomic radii, ion radii, ionization energy, and electronegativity. Have each member graph the data for one of the properties across the periods and describe the trend for that property across the periods. This can be an opportunity to use the graphing features of computer software programs or graphing calculators. The members then explain their graphs to the group. Teacher monitors student work and facilitates debriefing for the class. A written explanation of the trends and relationships can also be assessed. A variation on this activity is to make a three dimensional graph using drinking straws

and a 96 well plate. See Alternative 3-D Graph of Periodic Trends Task.

Because this lesson begins with exploring the trends in the properties, it will be necessary to provide explanation of these properties after this exploratory process. 10-2 discussion format can be used. Point out that ionization energies are given in kilojoules/mole of electrons. This is an opportunity to discuss how chemists use this fundamental quantity, the mole, for dealing with substances. (Refer to the unit, Finding Order, for related lessons on the mole and for instructions for the 10-2 strategy.)

Day 9

EQ: How are electrons arranged in energy levels, sublevels, and orbitals? Understanding: Atomic theory has been built on the measurements, observations, discoveries, and interpretations of data by many scientists, and has been modified over the centuries by both major discoveries and small modifications so that our current understanding of atomic structure is best explained by the wave-mechanics model using quantum numbers. Introduce this lesson with a video segment that reviews atomic theory and introduces the quantum atomic model (see resources). Teach electron arrangement by reviewing the contributions of Bohr, de Broglie, Schrödinger and Heisenberg. Direct students back to the atomic theory timelines they created in the unit, Finding Order.



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http://www.periodictable.com/pages/AAE_3d.html

http://chemlab.pc.maricopa.edu/periodic/spiraltable.html


Introduce the energy levels, sublevels, and orbitals using student handouts, text references, models, and/or diagrams. Guided note taking sheets could be used here as well. An analogy to a student’s home address can be used. Compare how knowing a student’s home address does not actually tell you where the student is at any given moment to an electron’s ground state quantum numbers describing the position of an electron. We could predict that the student will be in the vicinity of home frequently, but will not always be at home. The student may have suddenly acquired enough gasoline to travel-even to another state! The principal quantum number can be related to the state, the orbital quantum number can be related to the town. The magnetic quantum number can be related to the home’s street address (streets run out in many directions within a given town); the spin quantum number would correspond to the student’s name (no two people in the same house have exactly the same identity). The sudden acquisition of sufficient gasoline can be compared to quanta of energy. Students summarize by creating their own graphic organizer of this information on the quantum atom.

Days

10,11

EQ: How are electrons arranged in energy levels, sublevels, and orbitals? SC3b Understanding: Atomic theory has been built on the measurements, observations, discoveries, and interpretations of data by many scientists, and has been modified over the centuries by both major discoveries and small modifications so that our current understanding of atomic structure is best explained by the wave-mechanics model using quantum numbers. Activating strategy: Ask students to list examples of some patterns that occur in nature. Explain that chemists have described a general pattern for our understanding of electron distribution. Review energy levels, sublevels and orbitals from the previous lesson. Provide students with periodic table and guided practice handouts. Explain electron configuration. Begin with hydrogen, then helium, modeling on the board. Continue by modeling and explaining the pattern for the second period. Have students practice on elements in this period (series). Continue through the periods in this manner. Monitor students’ work to check for understanding of electron configuration. Teacher note: Differentiate as needed. It is not necessary for students to do the entire periodic table. However, some students may need the challenge of some of the more complex configurations while those who are struggling need more support from the teacher or a peer coach. Follow this same procedure for teaching orbital notation and Lewis electron dot notation. Allowplenty of time for distributed practice, monitoring and adjusting instruction to meet needs of students. A variation of this sequence would be to have the students complete the electron configuration for one element, then have a volunteer do it on the board to check. Then have students do five more and compare their answers with a partner. If there are differences, they should decide which one is correct and what the other one needs to do to correct. If they are unable to decide,then they ask the teacher. When they believe they have 5 correct, the teacher assesses. If all are



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correct, then they will need to do 5 more. If they are not correct, the teacher needs to provide guidance for the student to correct. Those that have 5 correct quickly should then be paired withthose that are struggling with the concept. The students should be able to design a “cheat sheet”of the pattern of electron configurations on their large block periodic table.

Summarizing strategy: Assign an element to each student. Have students write out the electron configuration, orbital notation, and Lewis dot structure as their ticket out the door. This can be differentiated based on the needs of the students.

Homework assignment: Prepare for electron configuration quiz to be given tomorrow.

Day

12

EQ: How can electron arrangement be used to identify substances? Understandings: • All matter possesses physical and chemical properties that are related to its atomic structure. • The modern atomic theory provides an explanation for the many patterns found in the properties of the elements, including atomic number, electron arrangement, reactivity, and bonding. • The periodic table, arranged by atomic number, reveals a tendency for properties to repeat in a periodic pattern (periodicity), and can be used to predict the properties and uses of an element. Give electron configuration quiz today. Activation strategy: This strategy will work best in a completely darkened room. Before turning out the lights, give student pairs two wintergreen mints (Find the mints that actually contain oil of wintergreen and DO NOT use sugar-free mints!) Instruct students to look directly at each other and bite down on their mint when the lights are turned out. If successful, they will see white-blue bursts of light. Use this event to begin discussion of the emission of electromagnetic radiation when electrons emit energy as they fall back to lower energy levels. Teacher note: For more information go to: http://chemistry.about.com/cs/howthingswork/a/aa060601a.htm Review Bohr’s thinking on energy and velocity of an electron. Discuss spectra (illustrate or show video); demonstrate spectrum tubes. Explain how atomic spectra lines are used to identify elements. Then present the Balmer series limerick.

Teacher note: One interactive source for demonstrating the Balmer series of hydrogen is found at http://www.avogadro.co.uk/light/bohr/spectra.htm. See also Line Spectrum Flash Tutorial. In this website go to the atomic structure section, which also includes a section on spectra and an electron notation flash tutorial. Ticket-out- the-door: Ask students to reflect on today’s lesson and propose ways that



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http://chemistry.about.com/cs/howthingswork/a/aa060601a.htm

http://www.avogadro.co.uk/light/bohr/spectra.htm

http://www.afn.org/%7Eafn02809

http://www.afn.org/%7Eafn02809

our knowledge of atomic spectra could be used in industry, medicine and astronomy. Teacher Note: The purpose of posing this question at the end of this class is to stimulate thinking for the next lesson. It is not necessary, nor advisable, to confirm students’ answers today. Day 12: If time allows, a day may be dedicated to a simulation of the spectral lines of an element. Examples of how this task can be done is found in many texts. A novel way to differentiate this task and to model atomic spectra is located at Gordon Conference Poster.

Day 13

EQ: How can electron arrangement be used to identify substances? o How can flame tests be used to identify metals? Understandings: • All matter possesses physical and chemical properties that are related to its atomic structure. • The modern atomic theory provides an explanation for the many patterns found in the properties of the elements, including atomic number, electron arrangement, reactivity, and bonding. • The periodic table, arranged by atomic number, reveals a tendency for properties to repeat in a periodic pattern (periodicity), and can be used to predict the properties and uses of an element. Remind students of the fireworks video clip, or reshow it or another clip. Use the previous day’s lesson to discuss the various colors seen in fireworks. Teacher note: A relevant attention grabbing demonstration to do UNDER A FUME HOOD is Zinc Pyrotechnics. Instructions and kits can be obtained from laboratory supply companies. Follow the strict safety instructions. Also see http://chemistry.about.com/od/fireworkspyrotechnics/ Have students conduct a flame test lab. There are many versions available for this lab. Choose a version from a laboratory manual or text.

Note on safety: Review and require students to follow all appropriate lab safety rules, including the wearing of goggles and aprons, fire safety, clothing safety and the safe handling of chemicals. Students must be thoroughly knowledgeable about the use of safety equipment including the shower, eyewash, sinks, and fire extinguisher.



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http://www.oakton.edu/user/%7Emwalter/playdoh/Gordon_Conference_Poster_5.htm


Teacher note: One strategy for maintaining lab hygiene and avoiding contamination of the solutions or of the wire loop is to organize this lab into stations, so that only one metallic ion is used per station, and the same wires can be used repeatedly without the nuisance of cleaning between each trial. Review lab safety with students before allowing them to begin lab. After lab, debrief. Tie this lab to the elements in the compounds used in fireworks. After the flame test lab assign and explain the culminating activity. Teacher note: Two possible tasks are given. Choose the one (or create your own) that suits your students’ needs and available time. To introduce the Toxitown activity, if time is available, have students read about a real life case where chemists helped identify a toxic hazard, or how spectral analysis is used in medicine, astronomy, or industry.

Research Project on Modern Lighting GRASP activity, Toxitown

Day 14

Give students time to organize their work for culminating task. Use part of class to review and summarize. Have students discuss answers to essential questions in groups. Share answers with class. Unit test will be given during the next class period. Alternatives for review: game show type review, flash cards, or cooperative test question

activity.

Day 15

Students complete a summative assessment to include a balance of types or items. Use any remaining time to work on culminating task.

Day 16,17

Presentation of culminating tasks. Teacher Note: Although day 16 is the last day of this unit, it may be scheduled a few days later in order to give students the time needed outside of class to complete the work. In the interim, another unit may be initiated. Also, re-teaching/retesting can be accommodated on these days.

Language to use: atomic number, electron configuration; orbital; isotope; mass number; average atomic mass, electron dot, ionization energy, electronegativity, atomic radius, emission spectrum, octet, period (series), family(group), periodic table, alkali metals, alkali earth metals, transition metals, nonmetals, metalloids, halogens, noble gases, inert, mole

Web Resources Sample List of Appropriate Resources for Unit: Finding Patterns A Science Odyssey: "Mysteries of the Universe" video produced by WBGH.



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A brief excerpt, from the video, related to modern atomic theory leading up to the advent of the quantum atom model and nature of the electron, can be found at: http://www.teachersdomain.org/9-12/sci/phys/fund/quantum/index.html. Site registration required, but free. Origins, A NOVA Presentation: "Back to the Beginning", produced by WGBH. “The Elements Forged in Stars”, a fast paced excerpt from the video, discusses/depicts the stellar events as samples of the elements are placed on the periodic table. http://www.teachersdomain.org/9-12/sci/ess/eiu/fusion/index.html.Site registration required, but free. www.keypress.com/chemistry/downloads/SampleLessons Re: periodic table lesson plansteachers.net/mentors/science/topic5162/6.30.06.17.36.16.html Teachers' Domain: Periodic Table of the Elements chart

http://chemistry.about.com/od/fireworkspyrotechnics/http://www.ci.natchitoches.la.us/Festival/Fireworks.asp http://www.sandlingfireworks.com/index.htmlhttp://chemlab.pc.maricopa.edu/periodic/spiraltable.htmlhttp://www.periodictable.com/pages/AAE_3d.htmlhttp://chemistry.about.com/cs/howthingswork/a/aa060601a.htmhttp://www.avogadro.co.uk/light/bohr/spectra.htm. http://www.oedilf.com/db/Lim.php?Word=Balmer%20serieshttp://www.afn.org/~afn02809/http://www.oakton.edu/user/~mwalter/playdoh/Gordon_Conference_Poster_5.htm

Additional Elements

Sample List of Appropriate Resources (optional) Misconceptions that this unit addresses: Students may have naïve or erroneous ideas about atomic structure including:

• the misconception that all atoms of the same element are identical • the misconception that electrons orbit the nucleus in fixed paths • the misconception that the more mass an atom has the larger it is • the misconception that the elements always exist in nature in their atomic form.

Unit Language atomic number, electron configuration; orbital; isotope; mass number; average atomic mass, electron dot, ionization energy; electronegativity; ionic radius; atomic radius; emission spectrum; octet



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http://www.teachersdomain.org/9-12/sci/phys/fund/quantum/index.html

http://www.teachersdomain.org/9-12/sci/ess/eiu/fusion/index.html

http://www.keypress.com/chemistry/downloads/SampleLessons

http://teachers.net/mentors/science/topic5162/6.30.06.17.36.16.html

http://www.teachersdomain.org/9-12/sci/phys/matter/ptablepr/index.html?action=%C2%A0%C2%A0View%C2%A0%C2%A0


http://www.ci.natchitoches.la.us/Festival/Fireworks.asp

http://www.sandlingfireworks.com/index.html


http://www.periodictable.com/pages/AAE_3d.html

http://chemistry.about.com/cs/howthingswork/a/aa060601a.htm

http://www.avogadro.co.uk/light/bohr/spectra.htm

http://www.oedilf.com/db/Lim.php?Word=Balmer%20series

http://www.afn.org/%7Eafn02809/

http://www.oakton.edu/user/%7Emwalter/playdoh/Gordon_Conference_Poster_5.htm

UNIT 2: FINDING PATTERNS APPENDIX OF PERFORMANCE TASKS FOR LEARNING AND ASSESSMENT

SC3-2 KWL: What do we know, need to know, and what did we learn about atomic structure? Suggested use: This task can be used In this unit the task is repeated after instruction on the wave-mechanics model of the atom to introduce the unit and revisited and completed as the unit unfolds.

Draw an Atom Learning Task: This task was begun in the Unit, Finding Order; in this unit, this task is repeated after instruction on the wave-mechanics model of the atom. Direct students to draw what they think an atom looks like. On the first day of learning about atomic structure, the student will make this drawing in his/her notebook along with the date. Along with the drawing, the student will give a written explanation of what they understand about the structure of the atom at this time. This activity will be repeated at appropriate intervals as the unit progresses and understanding increases. SC3; SCSh7c; SCSh8d. This activity is useful for activating thinking at the beginning of the lesson and for teacher monitoring for understanding and formative assessment. Student drawings and writings usually reveal misconceptions. The teacher can see what these misconceptions are, and incorporate instruction to address them.

Research project on Modern Lighting: Suggested use: This may be a culminating activity after the students have had experience with and explanation of spectrum tubes, flame tests, and emission spectra. The format might be a choice of written report, multi-media presentation, or demonstration with commentary. This may be done individually or it could be organized in groups of four, where each member is responsible for one type of lighting, (incandescent, fluorescent, inert gas, halogen), but the presentation is a group effort. For each type of lighting, the student should explain how the light produced is related to the emission of light energy from the movement of electrons in the atoms.

Develop a rubric that is consistent with the intended outcomes. GRASPS Activity: TOXITOWN After the student learns and practices the technique for conducting flame tests on a set of metallic ions, present the following GRASP scenario along with samples of the suspicious leakage. A new subdivision is being constructed in Toga County, just south of the old landfill on the edge of Toxitown. Last week several leaking containers were unearthed by a crew clearing land for a new home. Goal: To use appropriate science process skills to identify a substance by its chemical properties. Design and carry out a protocol for an initial analysis of the materials found in the containers to



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incorporate methods you have already learned. Investigate other methods for identifying elements or compounds. Roles: You are chemist working for the State Environmental Monitoring Agency (SEMA). You are a member of a team that consists of a project manager, a technology coordinator, a research analyst, and a senior chemist. You must agree on who has each role, but the work must be equally shared. Audience: The county commissioners of Toga County, Toxitown city council members, concerned citizens, and reporters from the Toxitown Tabloid. Situation: (Scenario) Your agency has been hired to test the questionable material and report the findings. The findings will be presented to the elected officials at a public community meeting. Product: The presentation should include your research, procedures, data, and analysis. This information should be presented both orally and graphically and as a written executive summary of the data and analysis. Appropriate technology should be used. Additionally, the report should address the limits of this analysis and suggest further tests that should be considered, explaining the type of test and what information could be obtained from the tests. Standards: SC3f, SCSh1a,b,c;SCSh2,SCSh3;SCSh4;SCSh6;SCSha,b Teacher Note: Choose an element that was included in the lab to build your story around. For example, you could include lithium chloride in the unknown solution. The color will be easy to detect in a flame test, and the students will discover that it has been used in treating certain mental illnesses when they begin to research the compound. This will give the students something to analyze in terms of safety, disposal and industrial responsibility. They can also determine how easy or hard it will be to dispose of the containers.

Average Atomic Mass AnalogyTell students that you have been looking at a particular classmate’s grades for this grading period. The student has nine grades of 95, and one grade of 10. If all grades count equally, what is this student’s average as of today? Allow students to calculate and explain their calculations. Then lead them to understand that 90% of the grades have a “grade mass” of 95, and 10% of the grades have a “grade mass” of 10. The average grade “mass” would be 86.5. Probe with questions such as, which grade has the most effect of the grade? Teacher Note: Students will usually take both sides in this discussion. This discussion will lead into the concept of relative abundance. Next have them calculate the grade if eight grades are 95.0, one grade is 94.5 and one grade is 94.1. Repeat the discussion and lead into average atomic mass of an element.



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Teacher Note: This task is effective as an activating strategy that leads directly into the teaching of average atomic mass. Average Atomic Mass Modeling Task Student groups use colored paper clips to represent pro-clips and neu-clips to build models of the three isoforms of clippium and record their relative mass. Each paper clip has a relative mass of one pcmu paper clip mass unit (pcmu). Clippium-1 has a clip mass of 1.0(one pro-clip). Clippium-2 has a clip mass of 2.0(one pro-clip and one neu-clip), and clippium-3 has a mass of 3.0 (one pro-clip and two neu-clips). After constructing these isoforms, give students the relative abundance of these isoforms (make these up; for example, the sample could be 95% Clippium-1; 3% Clippium-2; 2% Clippium-3). Have students calculate the average mass of the sample of clippium. Remember to address the issue of significant figures. (.95 * 1.0) + (.03 * 2.0) + (.02 * 3.0) = 1.07= 1.1 pcmu Give students the relative mass data for the isotopes of hydrogen, or other elements, and have them calculate the average atomic mass of the element. Relate this to molar mass of the element. (also relates to SC2c) Teacher note: This information is available in most chemistry texts as well as chemistry reference books. Wintergreen Mint Activity This is a fun activity with a connection to the emission of energy as electrons fall to lower levels, and a mini-lesson on lightning! Check the web for more information. One source: http://chemistry.about.com/cs/howthingswork/a/aa060601a.htm

Create the Periodic Table Activity There are various versions of this activity available from commercial and educational sources. However, it is easy to create your own unique version. Cover or remove all visible copies of the periodic table before beginning this activity. Prior to class create the element cards (a la Mendeleev). The set should contain sequences of elements from chosen groups (families), i.e. 1,2,17,18. On each card write the symbol, name, atomic number and selected properties of the element, but be sure that there is no indication on the card as to group. Include properties such as melting point, reaction with acids, and bases, metal/nonmetal, and atomic radii. Give a set of the cards to each collaborative group. The overall goal is to have the groups organize the elements into logical patterns based on the properties of the elements given on the cards. After arranging the elements, the group should conference with the teacher. During this conference, the students explain their arrangement. If the arrangement is logical and shows trends, then they can tape or glue their cards onto a larger sheet of paper to “create” their periodic table. Each group member must be able to explain the reasoning for the arrangement. Each group then shares their periodic table with the class. The teacher uses strategies to keep everyone engaged. For example, cut a deck of real playing cards for high (or low) card to determine who will report for the group.



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Group members should coach one another on their presentation, making sure that each member is capable of explaining their arrangement since any member of the group may be called upon to e the presenter, based on the luck of the draw. This strategy promotes peer coaching. b

Alternative 3-D Graph of Periodic Trends Task

Create an alternative three dimensional periodic table that satisfactorily illustrates the periodic properties of the elements. Use the 96 well-plate as a base to support drinking straws. Have students determine a reasonable scale for the length of straws to correspond to the needed values for atomic radii. For example, 1cm represents 1pm. Cut the straws to the appropriate length for each element in an assigned period of elements. Place straws in sequence in the well plate to create a 3-D graph of the trend. Repeat this process for ionic radii, ionization energy, and electronegativity. Also, if students have access to graphing calculators, graphing this data and tracing across the min and max to see trends within a family and across a period is an effective summarizing strategy. Element Survey Lab Students examine samples of elements representative of the element families and record properties on a blank periodic table chart. After completing this observation and data collection, students discuss patterns in the properties that they have discovered. Teacher note: Elements should be in closed vials. Sets can be assembled and used year after year.

Periodic Table Language Analysis Diagrams The following diagram can be adapted for previewing or developing any language term or concept. Following the first diagram there are three that are specifically designed for this task.

Ter AAAAAAAAAtomicA

TERM



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Trend across a period and why?

Exceptions? What is it?

Atomic Radius

Trend down the group and why?

Trend across a period: Explain.

What is it?

Exceptions? Explain.

Ionization Energy

Trend down the group: Explain.

Exceptions? Explain.

Trend across a period: Explain.

What is it?

Trend down the group: Explain.

electronegativity



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Element Silent Roundtable Task

This task is an example of an activating, team-building strategy. Each student will write with a different color marker. When instructed to start, one member of the group will write the name of an element on the board, then pass it to the right. Each member of the group will add one element to the list, then pass it on to the next member. If a member cannot think of an element, that member must think for at least 10 seconds before passing the board on. Continue to do this without talking, until the group cannot think of additional elements. Debrief: List the teams’ names across the top of a blackboard. Call on each group to offer one element. As each element is listed, other groups check it off. Each element that a team gets on the board is worth one point. Start each round with a different group, in order to give each group the advantage of going first. Groups may also challenge each other. (A common error is that a team will list an alloy or compound instead of an element.) If a challenge is correct, the challenging team gets the point. If the challenge is wrong, the team loses one point. If a team is not paying attention, and names an element that is already on the board they lose one point. Points can be used as bonus points for the team members with every student getting the total team points divided by the number of team members. A variation on this task is to repeat it using symbols rather than the names after students have been using the symbols in the context of the course, or after being assigned specific symbols to learn.

Teacher notes: 1. White boards can be made by cutting a piece of white shower board from a building supply company into squares with a table saw. Alternatives are laminated card stock or simply use a sheet of paper! 2. This activity might be extended as a review activity at the end of the unit from just producing names and/or symbols to grouping elements by family, solid/liquid (a very short list)/gas, reactivity within a family, atomic radii or other trends. The Periodic Table Salesman ( Selling The Ultimate Graphic Organizer) This is a GRASP task for the Finding Patterns Unit Goal: Explain the power of the periodic table to organize chemical information and predict the behavior of matter. Role: You are a periodic table salesman Audience: A physical science teacher Situation: The teacher has a limited budget and must choose between ordering beakers or a large periodic table for the classroom wall which comes with a set of activities for understanding the periodic table. Product: Produce a brochure, multimedia presentation, or a letter to remind the teacher of all the ways that the periodic table is the ultimate graphic organizer for understanding chemistry. Include the trends covered in class and how the teacher and students can make use of this information.

Mystery Element Task



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Each student will pick one element a write a description of it using the physical properties. This description can be extended to include researched characteristics, not immediately evident from this observation lab. Students write their descriptions on index cards or squares of paper. The description could be written as a riddle or a poem. (Haiku or diamante are interesting variations for the class literati.) If the class is working in groups, the sets of cards can be passed from group to group to be answered for practice. This is a good formative assessment opportunity. Balmer Series Limerick: Note from the referenced website: “We welcome efforts by others to spread the word about the OEDILF. If you choose to reproduce a limerick from our dictionary under the doctrine of fair use, we require that you credit the limerick's author.” Balmer series, Balmer, Johann by mike scholtes

Stars' spectra show shadows in series; Hence Balmer directed his queries To the spacing of lines Caused when hydrogen shines, Which led Doctor Bohr to his theories.

Johann Balmer (1825–1898) discovered a simple mathematical relationship that governs the wavelengths of hydrogen absorption (and emission) lines. This relationship was later explained by Niels Bohr's atomic theory, in which a hydrogen atom's one electron can occupy discrete energy levels. Bohr's theory led to the current quantum mechanical theory. The series corresponding to electrons leaving or returning to the ground state (n=1) is called the Lyman series, but its wavelengths are all in the ultraviolet. The Balmer series corresponds to electrons leaving or returning to the (n=2) energy level, and its lines are prominent in the visible-light spectra of most stars. Cooperative test questions: This activity gives students an investment in the test items and is a team building strategy. The teacher tells class that some of the items they write will be included on the test. If a student’s question is chosen, five (or more) points will automatically be added to the student’s test score.

Round one: Assign each group one essential question. Each student in the group makes up one selected response (multiple choice) test item that addresses the group’s essential question and writes the question on the front of an index card, and the answer on the back. The group members then quiz each other, and make sure that they all agree and understand the answers.

Round two: Each group passes their cards to the next group and who then answer the new set of questions.

Rounds three through : The process continues until the questions have traveled to each group.

To summarize the teacher takes up all cards and pulls some at random to ask to the class. (Use the name beaker).



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http://www.oedilf.com/db/Lim.php?Word=Balmer%20series

http://www.oedilf.com/db/Lim.php?Word=Balmer,%20Johann

http://www.oedilf.com/db/Lim.php?AuthorId=182

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