Coloring Agents of Fireworks

Names:

Natalie Pickering

 

Title of Lessons:

Emission Spectra (Benchmark Lesson)

 

Date of Lesson:

April 26th , 2005

April 28th , 2005

 

Length of Lesson:

2 days

 

Description of the Class:

            Name:  Chemistry

            Grade Level: Sophomore

            Schedule: Blocked (80 minute class)

 

Source of Lesson: 

Natalie Pickering 

http://imagine.gsfc.nasa.gov/docs/teachers/lessons/supernova/supernova_chemistry.html 

http://scidiv.bcc.ctc.edu/wv/spect/emission-flame-exp.html 

 

TEKS Addressed:

(1) Scientific processes. The student, for at least 40%
        of instructional time, conducts field and
        laboratory investigations using safe,
        environmentally appropriate, and ethical practices.
        The student is expected to:
            (A)  demonstrate safe practices during field and
             laboratory investigations; and
(2) Scientific processes. The student uses scientific
        methods during field and laboratory investigations.
        The student is expected to:
             (B)  collect data and make measurements with
             precision;
             (D)  organize, analyze, evaluate, make inferences,
             and predict trends from data; 
(E)                     communicate valid conclusions.
(4) Science concepts. The student knows the
        characteristics of matter. The student is expected
        to:
             (B)  analyze examples of solids, liquids, and gases
             to determine their compressibility, structure,
             motion of particles, shape, and volume;
 
             (D)  describe the physical and chemical
             characteristics of an element using the
             periodic table and make inferences about its
             chemical behavior.
 

Lesson Overview

Students learn about electromagnetic radiation, quantum theory, photons, and emission spectra through an interactive lecture.  They will expand and/or review what they have learned through an interactive website, which has further explanations and a spectroscopy simulation.  Students will then apply what they learned by conducting a Spectroscopy Lab. 

 

1ST DAY’S LESSON (April 13th)

 

Performance Objectives

The student will be able to:

·      Define wavelength, frequency, electromagnetic radiation, photons, quantum, spectra, ground state, excited state, etc.

·      Solve problems dealing with calculating wavelength, energy, frequency, and predicting color.

·      Identify and discuss the different types of electromagnetic radiation.

Resources, Materials, and Supplies Needed

Ø    Slide Show of “Sky at Many Wavelengths”

Ø    Lecture Notes

Ø    Student lecture notebooks

Ø    Website: http://scidiv.bcc.ctc.edu/wv/spect/emission-flame-exp.html 

Ø    Empty Outlines (1 per student)

Ø    Spectroscopy Lab Handout (1 per student)

Safety Considerations

None

Supplementary Materials, Handouts

            Lecture Notes (see attachment)

               Empty Outline

               Spectroscopy Lab Handout (see attachment)

Advance Preparations

            Read over lecture notes and prepare for lecture.  Have many example problems ready.  Make sure the simulation website is working.

                                                     

Modified 5E Model:

Teacher Does                                                         Student Does

Engagement:

 8:30—8:50am

Pre-Assessment:

Students view the slide presentation "The Sky at Many Wavelengths" and write at least five questions about the ideas presented in this slide show.

 

Go over student questions. (have students hand in their questions (no names) and exchange the papers.  Students read a question that is on the sheet they received.

Brief class discussion concerning ideas and answers.

 

Tell students that the next few days will hopefully lead them to more definite answers to these questions as well as questions concerning why different metals burn different colors.

 

 

 

 

Students watch slide show

 

 

 

 

Students write their questions down.

 

 

 

 

Students read a question aloud.

 

 

Students discuss.

 

 

 

Students listen.

Lecture:

8:50- 9:30 am

Lecture Students on the basics behind the Electromagnetic Spectrum.

 

Lecture Outline is provided as an attachment.  (Lecture Written Notes can be obtained…so hard to type them out).

 

Be interactive with lecture.  Help students take good notes, and give lots of examples.

Have students work in groups to solve example problems.

 

 

 

Students listen and take notes.

 

 

 

 

 

Students work in groups to solve example problems.

 

 

 

Simulation: 

9:30-9:50 am

Show students the Spect. Simulation on the computer.  Have students work in pairs to check out and play around on this website.  Students are required to turn in answers to the questions presented on the website. Students will turn these in end at the end of period.

 

 

Students working at computers.

 

 

 

Students answer the questions from the website.

 

Evaluation:

9:50-10:00am

CAT:  Have students construct complete the Empty Outline. 

Check over Outlines after class.

 

Have students also turn in the work they did from the website.  Check for completion.

 

Students should pick up a Spect Lab Handout.  They can read over it and be more prepared come Friday.

 

 

Dismiss class.

 

 

Students work individually on Empty Outline.

 

Students turn in their outlines.

 

Students turn in their work from the website.

 

 

Students get Spect Lab Handout and read over it at home.  They need to bring it back for lab on Friday.

 

Students leave.

 

 

2nd day of LESSON (April 15th)

 

Performance Objectives

Students will be able to:

·      Interpret and explain spectra of various elements.

·      Identify an unknown element or combination of elements by visible spectra.

·      Compare and Contrast Flame Test with Spectroscopy.

Resources, Materials, and Supplies Needed

               Per Class:

·      10 spectroscopes (Science Kit 45492 or 16525)

·      5 spectrum tubes (Science Kit 62999-01 -62999-55) (one of these should be mercury)

·      1 incandescent light bulb

·      1 "plant grow" light bulb

·      1 Compact Fluorescent light fixture

·      4 Chemical Light Sticks (each lasts four hours)

·      1 Standard Fluorescent light tube

·      5 Spectrum tube power supplies (Science Kit 62999 26)

·      10 Packages of colored pencils

Per Student:

   Spectroscopy Lab Handout (should already have from Wednesday)

Supplementary Materials, Handouts

               Spectroscopy Lab Handout (see attachment)

Advance Preparation:

               Have lab stations set up and ready. 

 

Lesson Organization

                               Teacher Does                                                                          Students Do

Pre-Explore:

8:30-8:45am

Teacher goes over Empty Outlines.

 

Explains to students that today they will be conducting a Spectroscopy Lab.  Define spectroscopy. 

Ask students to think of what chemists use spectroscopy for.

 

Go over general pre-lab rules and discussion of use of spectrometers, etc.:          

·      Students will have 4-5 minutes per station to collect data.

(Remember that about 1 out of 5 boys experience some degree of color-blindness. Usually, they should be able to see the bright lines, but they might misinterpret the color or think it's "white" light. Each pair of students should double-check each other, and avoid boy-boy pairs as much as possible. Many boys are unaware by this age that they may have a problem with particular colors, so be sensitive to the fact that some may "discover" their color-blindness during this activity.)

 

Have students get into groups of three and each group start at a different station.

 

 

Students listen.

 

Students listen.

Students guess that spectroscopy may be used for element identification and emission spectra.

 

 

Students listen to rules and watch demonstration.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Students get into groups and go to a station.

Explore:

8:45-9:40am

Teacher lets students begin working on the lab. Calls out when it is time for students to rotate to next station.

 

During Lab:

·      Caution students strongly about the need to avoid touching the gas tubes or the electrical power units. There is a very real chance that they could be burned or electrocuted if they directly touch the tubes. Make sure that the units are plugged into the GFI outlets.

·      Students need to keep safety glasses on throughout the activity. The gas tubes get very hot, and they can burst. Use a fluorescent light strip in the lab or an adjacent area as the fluorescent source.

·      For each pair or group, let one student observe the spectrum through the Spectrometer and call out the "bright line" wavelengths to their partner. The partner should double-check the line positions, and then the two of them should agree before they use the colored pencils to shade in the areas of their spectrum. They should change stations every 4 minutes in order to complete the activity in a period.

·      Some of the tubes will produce just line spectra, but most will have some degree of at least one part of the continual spectrum. This is because of the limited resolution of the diffraction grating used in the Spectrometers.

 

 

Students working at each station.

 

 

 

 

 

Students drawing and labeling the spectra of the gas that they see.

 

 

Students obeying safety rules.

 

 

 

 

 

 

 

 

Explain:

9:40-9:55am

Talk to students about the many different ways in which spectroscopy is used by modern scientists. Spectrometers of various forms represent the most important single group of lab instruments in the research lab today.

Allow students to compare their spectra for different tubes with other groups, and encourage them to discuss the differences and similarities. Ask students to draw relationships between what they said about light after the engagement activity (with the Sky at different Wavelengths) and what they discovered about light during the laboratory activity.

 

 

Students listen and discuss.

 

 

 

 

 

 

Students share their results with the class. 

 

Students might mention now how they realize light is quantum and not continuous but that our eyes see it as a continuum. Students may discuss how a certain color/wavelength sometimes predominates when looking at certain light/gas.

Evaluation:

9:55-10:00am

CAT:  Pro and Con Grid. Students individually compare the flame test with this procedure.

 

Students are to work on their post-lab questions at home.  The final lab report should be turned in on Monday.

 

Teacher dismisses class

 

 

Students work on Pro and Con grid.

 

 

 

Students work on post-lab questions at home.

Turn in lab report Monday

 

Students leave.