Outreach 2014

CANDAC Outreach

Title: Spectroscopy

Grade Level: Secondary

Subject: Science and Technology

Duration and frequency of activity: 60 minutes

Lesson at a glance

Students investigate various light spectra using a DVD spectroscope.

Focus question(s)

What is temperature? How do thermometers work? Is it possible to make a homemade thermometer?

Background

Temperature is the relative hotness or coldness that can be measured using a thermometer. It is also a measure of how fast the atoms and molecules of a substance are moving. Temperature is measured in degrees on the Fahrenheit, Celsius, and Kelvin scales, but we mainly use degrees Celsius to measure temperature in Canada. Homemade thermometer explanation: When the air inside the bottle expands, the pressure inside the bottle increases, pushing down on the liquid inside the bottle and pushing more liquid up the straw. When you cool the air again, it loses energy and decreases the pressure. The coloured water will then be pushed back down the straw by the pressure of the air outside.

Instructions

 



 

1. Review the electromagnetic spectrum with students. Use diagrams like the ones found at http://mynasadata.larc.nasa.gov/ElectroMag.html and http://www.yorku.ca/eye/spectru.htm to help explain radiation in terms of wavelength and frequency.

2. Distribute a spectroscope template and DVD to each student. Follow the instructions found in the article, “A DVD Spectroscope: A Simple, High-Resolution Classroom Spectroscope” (Wakabayashi and Hamada, 2006) to construct a DVD spectroscope.

3. Distribute the Spectroscope Activity Sheet and allow students about 10 minutes to practice using their spectroscopes by viewing emission spectra of sunlight, different classroom lights, and elemental discharge tubes (if you have them). Discuss their observations as a class by referring to the visible light spectrum and corresponding wavelengths.

4. Explain the CSI Nunavut activity to the class and give students about 15 minutes to complete the activity.

5. Discuss the findings of the CSI activity as a class and ask students to defend their verdict.

Materials

· spectroscope template (1 per student)

· scissors (for cutting out the spectroscopes)

· DVD (1 per student)

· various light sources (sunlight, incandescent and fluorescent bulbs, elemental discharge tubes, etc.)

Instructional method

· Kinesthetic activity

· Oral questioning

· Hands-on demonstration

Assessment

 

Demonstrates an understanding of temperature and how a thermometer works.

Participation in thermometer activity and discussion.

Helpful links

Use the article found athttp://www.sciencedaily.com/releases/2012/01/120119152353.htm to discuss global average temperature.

Extension/adaptations

Have students mark a scale for their thermometer. Either let students figure out how to mark a scale or give them instructions. They will need a real thermometer to do this. Instructions: Place a commercial thermometer next to your homemade one. Draw a line on the white card next to the water level in the straw. On this line, write the temperature you read on the commercial thermometer. Take the two thermomters to colder and warmer places, and record the commercial thermometer readings next to the water levels on your homemade scale. The more temperatures you record, the more exact your thermometer will be.

Source

University of Western Ontario: “Make your Own Thermometer!” Retrieved March 3, 2011 <http://publish.uwo.ca/~cagis/experiments/thermo.htm>.