![Page 1: © 2010 Pearson Education, Inc. Range of Visible Light Our eyes can see from 400 (blue/purple) to 700 (red) nm. Nm = nanometers = 10 -9 meters Our eyes](https://reader035.vdocuments.us/reader035/viewer/2022062721/56649f225503460f94c3b464/html5/thumbnails/1.jpg)
© 2010 Pearson Education, Inc.
Range of Visible Light
• Our eyes can see from 400 (blue/purple) to 700 (red) nm.
• Nm = nanometers = 10-9 meters
• Our eyes are most sensitive to yellow/green since that is the color of our sun
![Page 2: © 2010 Pearson Education, Inc. Range of Visible Light Our eyes can see from 400 (blue/purple) to 700 (red) nm. Nm = nanometers = 10 -9 meters Our eyes](https://reader035.vdocuments.us/reader035/viewer/2022062721/56649f225503460f94c3b464/html5/thumbnails/2.jpg)
© 2010 Pearson Education, Inc.
![Page 3: © 2010 Pearson Education, Inc. Range of Visible Light Our eyes can see from 400 (blue/purple) to 700 (red) nm. Nm = nanometers = 10 -9 meters Our eyes](https://reader035.vdocuments.us/reader035/viewer/2022062721/56649f225503460f94c3b464/html5/thumbnails/3.jpg)
© 2010 Pearson Education, Inc.
Continuous Spectrum
• The spectrum of a common (incandescent) light bulb spans all visible wavelengths, without interruption.
![Page 4: © 2010 Pearson Education, Inc. Range of Visible Light Our eyes can see from 400 (blue/purple) to 700 (red) nm. Nm = nanometers = 10 -9 meters Our eyes](https://reader035.vdocuments.us/reader035/viewer/2022062721/56649f225503460f94c3b464/html5/thumbnails/4.jpg)
© 2010 Pearson Education, Inc.
Emission Line Spectrum
• A gas cloud emits light only at specific wavelengths that depend on its composition and temperature, producing a spectrum with bright emission lines.
![Page 5: © 2010 Pearson Education, Inc. Range of Visible Light Our eyes can see from 400 (blue/purple) to 700 (red) nm. Nm = nanometers = 10 -9 meters Our eyes](https://reader035.vdocuments.us/reader035/viewer/2022062721/56649f225503460f94c3b464/html5/thumbnails/5.jpg)
© 2010 Pearson Education, Inc.
Absorption Line Spectrum
• A cloud of gas between us and a light bulb can absorb light of specific wavelengths, leaving dark absorption lines in the spectrum.
![Page 6: © 2010 Pearson Education, Inc. Range of Visible Light Our eyes can see from 400 (blue/purple) to 700 (red) nm. Nm = nanometers = 10 -9 meters Our eyes](https://reader035.vdocuments.us/reader035/viewer/2022062721/56649f225503460f94c3b464/html5/thumbnails/6.jpg)
© 2010 Pearson Education, Inc.
How does light tell us what things are made of?
![Page 7: © 2010 Pearson Education, Inc. Range of Visible Light Our eyes can see from 400 (blue/purple) to 700 (red) nm. Nm = nanometers = 10 -9 meters Our eyes](https://reader035.vdocuments.us/reader035/viewer/2022062721/56649f225503460f94c3b464/html5/thumbnails/7.jpg)
© 2010 Pearson Education, Inc.
Chemical Fingerprints
• Each type of atom has a unique set of energy levels.
• Each transition corresponds to a unique photon energy, frequency, and wavelength.
Energy levels of hydrogen
![Page 8: © 2010 Pearson Education, Inc. Range of Visible Light Our eyes can see from 400 (blue/purple) to 700 (red) nm. Nm = nanometers = 10 -9 meters Our eyes](https://reader035.vdocuments.us/reader035/viewer/2022062721/56649f225503460f94c3b464/html5/thumbnails/8.jpg)
© 2010 Pearson Education, Inc.
![Page 9: © 2010 Pearson Education, Inc. Range of Visible Light Our eyes can see from 400 (blue/purple) to 700 (red) nm. Nm = nanometers = 10 -9 meters Our eyes](https://reader035.vdocuments.us/reader035/viewer/2022062721/56649f225503460f94c3b464/html5/thumbnails/9.jpg)
© 2010 Pearson Education, Inc.
• Downward transitions produce a unique pattern of emission lines.
Chemical Fingerprints
![Page 10: © 2010 Pearson Education, Inc. Range of Visible Light Our eyes can see from 400 (blue/purple) to 700 (red) nm. Nm = nanometers = 10 -9 meters Our eyes](https://reader035.vdocuments.us/reader035/viewer/2022062721/56649f225503460f94c3b464/html5/thumbnails/10.jpg)
© 2010 Pearson Education, Inc.
• Because those atoms can absorb photons with those same energies, upward transitions produce a pattern of absorption lines at the same wavelengths, producing an absorption spectrum.
Chemical Fingerprints
![Page 11: © 2010 Pearson Education, Inc. Range of Visible Light Our eyes can see from 400 (blue/purple) to 700 (red) nm. Nm = nanometers = 10 -9 meters Our eyes](https://reader035.vdocuments.us/reader035/viewer/2022062721/56649f225503460f94c3b464/html5/thumbnails/11.jpg)
© 2010 Pearson Education, Inc.
Chemical Fingerprints
• Various emission spectra.
![Page 12: © 2010 Pearson Education, Inc. Range of Visible Light Our eyes can see from 400 (blue/purple) to 700 (red) nm. Nm = nanometers = 10 -9 meters Our eyes](https://reader035.vdocuments.us/reader035/viewer/2022062721/56649f225503460f94c3b464/html5/thumbnails/12.jpg)
© 2010 Pearson Education, Inc.
Clicker Question
Which letter labels the peak (greatest intensity) of infrared light?
![Page 13: © 2010 Pearson Education, Inc. Range of Visible Light Our eyes can see from 400 (blue/purple) to 700 (red) nm. Nm = nanometers = 10 -9 meters Our eyes](https://reader035.vdocuments.us/reader035/viewer/2022062721/56649f225503460f94c3b464/html5/thumbnails/13.jpg)
© 2010 Pearson Education, Inc.
Clicker Question
Which letter labels the peak (greatest intensity) of infrared light?
![Page 14: © 2010 Pearson Education, Inc. Range of Visible Light Our eyes can see from 400 (blue/purple) to 700 (red) nm. Nm = nanometers = 10 -9 meters Our eyes](https://reader035.vdocuments.us/reader035/viewer/2022062721/56649f225503460f94c3b464/html5/thumbnails/14.jpg)
© 2010 Pearson Education, Inc.
Clicker Question
Which letter labels emission lines?
![Page 15: © 2010 Pearson Education, Inc. Range of Visible Light Our eyes can see from 400 (blue/purple) to 700 (red) nm. Nm = nanometers = 10 -9 meters Our eyes](https://reader035.vdocuments.us/reader035/viewer/2022062721/56649f225503460f94c3b464/html5/thumbnails/15.jpg)
© 2010 Pearson Education, Inc.
Clicker Question
Which letter labels emission lines?