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Science Exploration Guidesheet
Science Explorations (continued)
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Spectroscopic ObservationsSpectroscopic Observations
Spectroscopic ObservationsSpectroscopic Observations
Spectroscopic Observations
For these activities students will construct their own spectroscope, observe common light
sources, record their spectra and compare their findings with fellow classroom scientists.
For directions to build a spectroscope, see the Spectroscope Poster (purchase information
found in the Materials List. Allow approximately 3 class sessions to construct and calibrate
the spectroscopes before having students perform these science explorations.
Unlike a prism, which disperses white light into the rainbow colors through refraction, the
diffraction grating used in this homemade spectroscope disperses white light through a
process called
interference
The grating used for this spectroscope consists of a transpar-
ent piece of plastic with many thousands of microscopic parallel grooves. Light passing
between these grooves is dispersed into its component wavelengths and appears as paral-
lel bands of color on the retina of the observer’s eyes.
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Spectroscopic Observation #1: Observing SpectraSpectroscopic Observation #1: Observing Spectra
Spectroscopic Observation #1: Observing SpectraSpectroscopic Observation #1: Observing Spectra
Spectroscopic Observation #1: Observing Spectra
Students observe common light sources, record their spectra and compare their findings
with fellow classroom scientists.
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Spectroscopic Observation #2: Mystery Gas TubesSpectroscopic Observation #2: Mystery Gas Tubes
Spectroscopic Observation #2: Mystery Gas TubesSpectroscopic Observation #2: Mystery Gas Tubes
Spectroscopic Observation #2: Mystery Gas Tubes
Teacher purchases in advance 3 - 5 gas tubes (recommended helium, hydrogen, mercury,
neon and water). Do not tell the students what gas is found in each gas tube. Have stu-
dents observe each tube using their spectroscopes and record their findings. Then, have
the students compare each spectrum with the
Spectra Reference Chart
(located on the
Web site or available to be printed on a color printer from this PDF file). Students can next
determine which gas is contained in each tube by comparing the spectra they observe and
record to the reference chart.
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Spectroscopic Observation #3: Solar SpectrumSpectroscopic Observation #3: Solar Spectrum
Spectroscopic Observation #3: Solar SpectrumSpectroscopic Observation #3: Solar Spectrum
Spectroscopic Observation #3: Solar Spectrum
Have students observe sunlight through their spectroscopes by using a white wall to reflect
the sun’s light.
Do NOT have students view the sun directly through their spectroscopes.Do NOT have students view the sun directly through their spectroscopes.
Do NOT have students view the sun directly through their spectroscopes.Do NOT have students view the sun directly through their spectroscopes.
Do NOT have students view the sun directly through their spectroscopes.
Students record the solar spectrum. Next, have students compare their solar spectrum with
an actual solar spectrum from the
Spectra Reference Chart.
These will be different simply
because of the difference in quality between the homemade device and the more precise
scientific instrument. Then, review with the students the directions on how to identify ele-
ments in the solar spectrum from the Student Guideheet:
Solar Spectrum.
Finally, have the
students follow the same procedure and attempt to determine the other elements found in
the sun.