I tried this activity abd had little success. I tried one indorr light and two outdorr light and it seemed to me I got the same broad spectrum. I found it difficult to take the photos either the flash obliterated the image or with no flash I had veryu blurry pictures.
A teacher at my school has different fluroscent tubes with different gases which you can look at through diffraction gratings and see different spectrums. We use it to show the different nergy levels of electrons in atoms. When he leaves he will take the equipment with him I hope he doesn't leave soon.
We too have gas filled bulbs for use in our chemistry classes. I have printed emission spectra for my students to see, then put different tubes in for the students to view through spectroscopes. They draw what they see (starting with the 4 lines of Hydrogen, then moving on to more difficult spectra). Then on test day, I put in an 'unknown' bulb and ask students to identify the gas in the bulb by comparing to known emmission spectra.
For physics, we can use this diffraction grating to analyze different light sources and have them 'guess' what gasses are in the source - i.e. the sodium vapor street lamps should contain a large amount of sodium - how does it compare to a bulb with pure sodium vapor? What other gasses may exist? Does it change the color of light emitted?
I can use this activity as a reinforcement of a Flame Test Experiment (done in a dark room). Each group will be given a set of chloride solutions ( CaCl2, SrCl2, LiCl). Students will compare the spectrum of each flame using the Night Quest Spectra. Then they will capture the image (spectrum) using a camera. The spectrum will also be compared with the spectrum on this website http://jersey.uoregon.edu/vlab/elements/Elements.html
I enjoyed this activity. I have always had my students use the spectral discharge tubes to draw the spectra of common elements and then also of fluorescent lights in the classroom and reflected sunlight. But I like the idea of having students take a grating home with them and snapping photos around the house. I though it was neat to see the difference in the lighting around my house and it was fun to use the camera for “homework”. As for how to use this with a class, it would be neat to compile everyone’s images and see if we could get examples of each type of lamp on the Night Quest Card.
I couldn’t get good photos inside the house. Outside was definitely easier. I found that the farther away the light, the better the photo because the light wasn’t blinding the camera. Also, it was much easier once I made a frame/holder for the diffraction grating out of some cardboard.
I had little success with viewing the spectra. I eventually ended up taping the diffraction grating to my camera, which worked pretty well. I'm not sure if it was the lights I looked at, or the poor quality of my pictures but I was unable to identify my light sources. They all looked continuous. Ad--What was your secret?!?! Your results are beautiful!
I was also thinking about how this would make a great extension of a flame test lab. I would have students snap pictures of their flame spectra and then use a data bank of atomic spectra to identify them. I'm very excited to try this out. I think elemental spectra will work better than light source spectra.
I can simplify this Night Quest activity for my elemntary kids.
With the group, I'll ask my kids to shine a flashlight through the diffraction grating. I will aks them to answer the following questions:
What colors do you see? Record the different colors, the order in which they appear, and their wavelengths
Then I'll ask them to fill a container with water and shine a flashlight so that the light beam shines through the water. Kids will turn the lights off and observe the light beam from the side and the end of the container. They can view the light beam directly or project the light onto a white card. And they will answer this question: What color is the light?
They will add small amounts of powdered milk and mix until they can see the beam shining through the liquid. Then they will observe the light again from the side and the end of the container. Then they will answer these questions:
What color(s) do you see now? Compare the colors viewed from the side and the end.
Then I will let them to use the demostration to explain in their own words why they see a blue sky and a yellowish orange sun... Why do you think the sun appears white at noon and orange or red at sunset?
Students will observe various lights using diffraction grating. These light sources include tubes that have been filled with various types of gases. As electricity passes through these tubes, the gas glows and light is given off. Students will compare the spectra of these gases with incandescent sources and fluorescent light sources. Then they will identify the gases that is used to fill the fluorescent light tubes. Using the spectrometer, students will sketch what they see and they will mark the wavelength that defined each color region. They will sketch the range of colors observed using the colored pencils and note the regions where the colors are most bright and most dim. They will follow the said steps in different light sources (gas tubes, fluorescent, incandescent and chemical light sticks)
My students will observe the continuous spectra of light bulbs and fluorescent lights and they will differentiate the 2 spectra.
I can also ask them to observe the spectrum produce by neon signs, sodium vapor lights, and mercury vapor lights. They will write the difference between these spectra and those from light bulbs?
In the chemistry lab of our school, my kids can work on different gas vapor lamps containing hydrogen, helium, neon, or argon. Each group will discuss why are the spectra of these gases not continuous like the spectra of a light bulb or the sun?.
This would be a really neat addition to my unit on electromagnetic radiation and atomic orbitals. Before the flame lab I would introduce my students to the diffraction grating just so they could observe the components of sunlight. (This would help demonstrate that colors of light have different wavelengths.) Then we would do the traditional flame lab (various salts are held over flame to determine their identifying colors). I have the students identify a couple of unknown salts based on their colors. Then I would ask them to bring back pictures of various light sources using the diffraction grating, and we would identify the type of light in class (and relate this to the unknown salts in the flame lab). Then, I would have students postulate how astronomers figure out the composition of the sun and other extraterrestrial light sources. I would also ask them how this type of research is limiting, and I would hope they bring up dark matter!
When I taught chemistry I used the gas emission tubes and homemade spectroscopes (you can make surprising good quantitative spectrometers from shoeboxes with a small piece of diffraction grating and a clear plastic ruler placed in cutouts on one end!). The picture that I took this time that I liked the most was a compact fluorescent bulb - rather than seeing clear vertical lines, you see the image of the squiggly-shaped bulb, not as a continuous spectrum, but as specific colored images - very cool! The catch with doing thos activity with students is sending them home with large enough pieces of grating to take the picture (because the frame REALLY helps) - that could get expensive considering the number that would be lost or damaged.
University of Illinois chemistry professor Alexander Scheeline developed a cell-phone spectrometer for high school chemistry classes. He wrote free software that analyzes JPEG images taken by students' cellular phones.
Go to http://www.asdlib.org/onlineArticles/elabware/Scheeline_Kelly_Spectrophotometer/index.html and click on Executable software. The program will download onto your pc. If you click on student module there is a pdf with instructions. The actual instructions for analyzing your spectra can be found on page 5 beginning "After the JPGs are in place".
Try this out if you have time. My students enjoy taking photos of spectra. Now we can analyze the jpeg images of spectra.
Chris, thanks for the link for the cell phone spectrometer. I was thinking that this assignment would be very good for my high school students as they all have cell phones that take pictures and it would be great to have them submit pictures taken at night.
I had my best results at night. I had my spouse drive me around with the camera and diffraction grating and I had a great time seeing the differences in spectra (even if I couldn't photograph it very well). I realize that was probably what I was supposed to do in assignment 1. Better late than never. I wish I had taken the spectroscope with me on my drive.
Looking at my pictures, this is what I think I'm seeing. It looks as if we are seeing the full spectrum most of the time, however, when I am looking at some of the spectra for some parking lot lights, I see what I was calling nodes. Some of the spectra didn't look smooth (straight up and down), but looked bumpy. I assume that these would appear as spectral lines in a spectroscope.
I am out of town at the moment and am excited to get home and take my spectroscope "on the road" and try the cell phone spectrometer. I really want to use that with my class!
I took several pictures, and compared the colors that was produced using the diffraction grating, most of the pictures I got have Continuous spectrum they have smooth gradation of colors, with no distinct features and lines. When I compared the colors to the spectra produced by individual elements in the periodic table at: http://jersey.uoregon.edu/vlab/elements/Elements.html. I found out that most of the colors from my pictures contained mostly alkali metal in particular Cesium and Franciun, as we all know the alkali metals are softer than most other metals and Cesium and francium are the most reactive elements in the alkali metal group.
What I did with my HS students with special needs, we covered the windows and all sources of sunlight to keep the classroom dark and I let them use the diffraction grating to look at the different light sources such us fluorescent light, computer screen, candle light, flashlight, active board and even the light from the microwave. They shared their observations to class and it was really a fun activity for them. It so happened that we were reading a story in our Reading block entitled “Zaaaaaap,“ which is about the use of lightning as a source of electric power so I was able to connect the activity.
I tried to take pictures of some incandescent lights outside, incandescent lights inside, and xenon and fluorescent lamps inside . The outside pictures did not turn out nor did the xenon headlights. The inside incandescent and fluorescent made the best pictures. I’m glad I made a holder for my diffraction grating for an earlier module, otherwise it would have been harder to get a picture while holding the camera and the grating. I have used the diffraction gratings in a lab before where the students calculate the wavelengths of the different colors of light using an incandescent bulb. I could use the same diffraction gratings, which are small and mounted on old fashion slide cardboard, and have them take them home and take pictures of various light sources using their cell phone cameras.
The following is a description of how I ran this activity with my students. I will resend the pictures to Chris.
I first had them look at several different gas sources, the images Gas Source.JPG is of a Helium source. The students observed that the light coming from these gas sources consists of discrete bands of light instead of a continuous rainbow.
In addition to the many gas sources that we looked out I signed out Mercury as being of particular interest and drew the students attention to the spectra in the fluorescent bulbs overhead having them carefully look from one to another. The whitish glow from the material covering the floruscent bulbs makes the mercury lines difficult to detect but students can eventually see the sets of lines in both different locations. These images didn't really come out a nicely as I would like them to be, I imagine that a black piece of paper with slit cut through it could help the resolution quite a bit if placed in between object and grating. In any case ``Mercury.Jpg'' is the image of the mercury source and ``incandescent Light.jpg'' is the image of the incandescent light source.
I tried to take a picture of a few incandescent light sources and none of them turned out well at all. Again, I imagine that a black barrier with a slit could help to improve the quality of the photography quite a bit. ``Incandescent Light.jpg'' is typical of my efforts. I also spent some time trying to photograph the sun, which was not fruitful.
Finally I did not have my students do this when they were using the gratings to investigate different light sources but I used the grating to take a picture of my cell phone. I expected to see the screen split into red, green, and blue color images so I was a little surprised to see something approximating five different colors in a cell phone. I'm unsure why you would engineer a screen to use five colors instead of the minimum three but I image, corporations being what they are, that there must be some money to be saved from this process. ``Cell phone.jpg'' shows this image.
I tried this activity abd had little success. I tried one indorr light and two outdorr light and it seemed to me I got the same broad spectrum. I found it difficult to take the photos either the flash obliterated the image or with no flash I had veryu blurry pictures.
ReplyDeleteA teacher at my school has different fluroscent tubes with different gases which you can look at through diffraction gratings and see different spectrums. We use it to show the different nergy levels of electrons in atoms. When he leaves he will take the equipment with him I hope he doesn't leave soon.
We too have gas filled bulbs for use in our chemistry classes. I have printed emission spectra for my students to see, then put different tubes in for the students to view through spectroscopes. They draw what they see (starting with the 4 lines of Hydrogen, then moving on to more difficult spectra). Then on test day, I put in an 'unknown' bulb and ask students to identify the gas in the bulb by comparing to known emmission spectra.
ReplyDeleteFor physics, we can use this diffraction grating to analyze different light sources and have them 'guess' what gasses are in the source - i.e. the sodium vapor street lamps should contain a large amount of sodium - how does it compare to a bulb with pure sodium vapor? What other gasses may exist? Does it change the color of light emitted?
I can use this activity as a reinforcement of a Flame Test Experiment (done in a dark room). Each group will be given a set of chloride solutions ( CaCl2, SrCl2, LiCl). Students will compare the spectrum of each flame using the Night Quest Spectra. Then they will capture the image (spectrum) using a camera. The spectrum will also be compared with the spectrum on this website http://jersey.uoregon.edu/vlab/elements/Elements.html
ReplyDeleteI’m so proud of my results, I have to share them.
ReplyDeletehttps://picasaweb.google.com/105074365867712124942/UntitledAlbum
I enjoyed this activity. I have always had my students use the spectral discharge tubes to draw the spectra of common elements and then also of fluorescent lights in the classroom and reflected sunlight. But I like the idea of having students take a grating home with them and snapping photos around the house. I though it was neat to see the difference in the lighting around my house and it was fun to use the camera for “homework”. As for how to use this with a class, it would be neat to compile everyone’s images and see if we could get examples of each type of lamp on the Night Quest Card.
I couldn’t get good photos inside the house. Outside was definitely easier. I found that the farther away the light, the better the photo because the light wasn’t blinding the camera. Also, it was much easier once I made a frame/holder for the diffraction grating out of some cardboard.
I had little success with viewing the spectra. I eventually ended up taping the diffraction grating to my camera, which worked pretty well. I'm not sure if it was the lights I looked at, or the poor quality of my pictures but I was unable to identify my light sources. They all looked continuous. Ad--What was your secret?!?! Your results are beautiful!
ReplyDeleteI was also thinking about how this would make a great extension of a flame test lab. I would have students snap pictures of their flame spectra and then use a data bank of atomic spectra to identify them. I'm very excited to try this out. I think elemental spectra will work better than light source spectra.
I can simplify this Night Quest activity for my elemntary kids.
ReplyDeleteWith the group, I'll ask my kids to shine a flashlight through the diffraction grating.
I will aks them to answer the following questions:
What colors do you see? Record the different colors, the order in which they appear, and their wavelengths
Then I'll ask them to fill a container with water and shine a flashlight so that the light beam shines through the water. Kids will turn the lights off and observe the light beam from the side and the end of the container. They can
view the light beam directly or project the light onto a white card. And they will answer this question: What color is the light?
They will add small amounts of powdered milk
and mix until they can see the beam
shining through the liquid. Then they will observe the light again from the side and the end of the container. Then they will answer these questions:
What color(s) do you see now? Compare the colors viewed from the side and the end.
Then I will let them to use the demostration to explain in their own words why they see a blue sky and a yellowish orange sun...
Why do you think the sun appears white
at noon and orange or red at sunset?
Students will observe various lights using diffraction grating. These light sources include tubes that have been filled with various types of gases. As electricity passes through these tubes, the gas glows and light is given off. Students will compare the spectra of these gases with incandescent sources and fluorescent light sources. Then they will identify the gases that is used to fill the fluorescent light tubes.
ReplyDeleteUsing the spectrometer, students will sketch what they see and they will mark the wavelength that defined each color region. They will sketch the range of colors observed using the colored pencils and note the regions where the colors are most bright and most dim. They will follow the said steps in different light sources (gas tubes, fluorescent, incandescent and chemical light sticks)
My students will observe the continuous spectra of light bulbs and fluorescent lights and they will differentiate the 2 spectra.
ReplyDeleteI can also ask them to observe the spectrum produce by neon signs, sodium vapor lights, and mercury vapor lights. They will write the difference between these spectra and those from light bulbs?
In the chemistry lab of our school, my kids can work on different gas vapor lamps containing hydrogen, helium, neon, or argon. Each group will discuss why are the spectra of these gases not continuous like the spectra of a light bulb or the sun?.
This would be a really neat addition to my unit on electromagnetic radiation and atomic orbitals. Before the flame lab I would introduce my students to the diffraction grating just so they could observe the components of sunlight. (This would help demonstrate that colors of light have different wavelengths.) Then we would do the traditional flame lab (various salts are held over flame to determine their identifying colors). I have the students identify a couple of unknown salts based on their colors. Then I would ask them to bring back pictures of various light sources using the diffraction grating, and we would identify the type of light in class (and relate this to the unknown salts in the flame lab). Then, I would have students postulate how astronomers figure out the composition of the sun and other extraterrestrial light sources. I would also ask them how this type of research is limiting, and I would hope they bring up dark matter!
ReplyDeleteBob's (Robert_John) extension of this is very similar to the demo I've done for astronomy students to explain interstellar reddening - same principle!
ReplyDeleteWhen I taught chemistry I used the gas emission tubes and homemade spectroscopes (you can make surprising good quantitative spectrometers from shoeboxes with a small piece of diffraction grating and a clear plastic ruler placed in cutouts on one end!). The picture that I took this time that I liked the most was a compact fluorescent bulb - rather than seeing clear vertical lines, you see the image of the squiggly-shaped bulb, not as a continuous spectrum, but as specific colored images - very cool! The catch with doing thos activity with students is sending them home with large enough pieces of grating to take the picture (because the frame REALLY helps) - that could get expensive considering the number that would be lost or damaged.
ReplyDeleteNow you can analyze your pictures!
ReplyDeleteUniversity of Illinois chemistry professor Alexander Scheeline developed a cell-phone spectrometer for high school chemistry classes. He wrote free software that analyzes JPEG images taken by students' cellular phones.
http://www.news.illinois.edu/news/10/1007scheeline_spectrophotometry.html
Unfortunately, this program doesn't work on macs.
Go to http://www.asdlib.org/onlineArticles/elabware/Scheeline_Kelly_Spectrophotometer/index.html
and click on Executable software. The program will download onto your pc. If you click on student module there is a pdf with instructions. The actual instructions for analyzing your spectra can be found on page 5 beginning "After the JPGs are in place".
Try this out if you have time. My students enjoy taking photos of spectra. Now we can analyze the jpeg images of spectra.
Chris
Chris, thanks for the link for the cell phone spectrometer. I was thinking that this assignment would be very good for my high school students as they all have cell phones that take pictures and it would be great to have them submit pictures taken at night.
ReplyDeleteI had my best results at night. I had my spouse drive me around with the camera and diffraction grating and I had a great time seeing the differences in spectra (even if I couldn't photograph it very well). I realize that was probably what I was supposed to do in assignment 1. Better late than never. I wish I had taken the spectroscope with me on my drive.
Looking at my pictures, this is what I think I'm seeing. It looks as if we are seeing the full spectrum most of the time, however, when I am looking at some of the spectra for some parking lot lights, I see what I was calling nodes. Some of the spectra didn't look smooth (straight up and down), but looked bumpy. I assume that these would appear as spectral lines in a spectroscope.
I am out of town at the moment and am excited to get home and take my spectroscope "on the road" and try the cell phone spectrometer. I really want to use that with my class!
I took several pictures, and compared the colors that was produced using the diffraction grating, most of the pictures I got have Continuous spectrum they have smooth gradation of colors, with no distinct features and lines. When I compared the colors to the spectra produced by individual elements in the periodic table at: http://jersey.uoregon.edu/vlab/elements/Elements.html. I found out that most of the colors from my pictures contained mostly alkali metal in particular Cesium and Franciun, as we all know the alkali metals are softer than most other metals and Cesium and francium are the most reactive elements in the alkali metal group.
ReplyDeleteWhat I did with my HS students with special needs, we covered the windows and all sources of sunlight to keep the classroom dark and I let them use the diffraction grating to look at the different light sources such us fluorescent light, computer screen, candle light, flashlight, active board and even the light from the microwave. They shared their observations to class and it was really a fun activity for them. It so happened that we were reading a story in our Reading block entitled “Zaaaaaap,“ which is about the use of lightning as a source of electric power so I was able to connect the activity.
From John Webster
ReplyDeleteI tried to take pictures of some incandescent lights outside, incandescent lights inside, and xenon and fluorescent lamps inside . The outside pictures did not turn out nor did the xenon headlights. The inside incandescent and fluorescent made the best pictures. I’m glad I made a holder for my diffraction grating for an earlier module, otherwise it would have been harder to get a picture while holding the camera and the grating.
I have used the diffraction gratings in a lab before where the students calculate the wavelengths of the different colors of light using an incandescent bulb. I could use the same diffraction gratings, which are small and mounted on old fashion slide cardboard, and have them take them home and take pictures of various light sources using their cell phone cameras.
The following is a description of how I ran this activity with my students. I will resend the pictures to Chris.
ReplyDeleteI first had them look at several different gas sources, the images Gas Source.JPG is of a Helium source. The students observed that the light coming from these gas sources consists of discrete bands of light instead of a continuous rainbow.
In addition to the many gas sources that we looked out I signed out Mercury as being of particular interest and drew the students attention to the spectra in the fluorescent bulbs overhead having them carefully look from one to another. The whitish glow from the material covering the floruscent bulbs makes the mercury lines difficult to detect but students can eventually see the sets of lines in both different locations. These images didn't really come out a nicely as I would like them to be, I imagine that a black piece of paper with slit cut through it could help the resolution quite a bit if placed in between object and grating. In any case ``Mercury.Jpg'' is the image of the mercury source and ``incandescent Light.jpg'' is the image of the incandescent light source.
I tried to take a picture of a few incandescent light sources and none of them turned out well at all. Again, I imagine that a black barrier with a slit could help to improve the quality of the photography quite a bit. ``Incandescent Light.jpg'' is typical of my efforts. I also spent some time trying to photograph the sun, which was not fruitful.
Finally I did not have my students do this when they were using the gratings to investigate different light sources but I used the grating to take a picture of my cell phone. I expected to see the screen split into red, green, and blue color images so I was a little surprised to see something approximating five different colors in a cell phone. I'm unsure why you would engineer a screen to use five colors instead of the minimum three but I image, corporations being what they are, that there must be some money to be saved from this process. ``Cell phone.jpg'' shows this image.