I did this expirement with Natasha Oslinger on 9/15/14. The goal of this experiment was to see the how compounds react when mixed with methanol and set ablaze.
Pre-Lab Questions
What color of light is the lowest in energy?
The protons emit a red light at their lowest visible energy.
What color of light is the highest in energy?
The protons emit a violet light at their highest visible energy.
What color of light is the highest frequency?
The protons emit a violet light at their highest frequency.
What color of light is the lowest frequency?
The proton emit a red light at their lowest frequency.
How are electrons “excited”?
Electrons are excited when they absorb energy, such as when they’re being heated in a flame.
What does it mean when the electrons are “excited”?
It means they’re in a higher energy proton shell.
In your own words, write a short explanation of how an electron absorbs energy and re-emits it as light and why different elements have different spectra.
Electrons absorb energy in two different ways. In the first, an electron can be absorb a photon with the precise amount of energy that is needed to move from one quantum shell from another. In the second way is to heat the electrons. When heated, the electrons begin to absorb energy from the heat. When it begins to lose it’s energy, an electron releases a photon of light, a particle of pure energy. The difference between the ground state and the excited energy level with each element, is what causes different elements to have different spectra.
Pre-Lab Questions
What color of light is the lowest in energy?
The protons emit a red light at their lowest visible energy.
What color of light is the highest in energy?
The protons emit a violet light at their highest visible energy.
What color of light is the highest frequency?
The protons emit a violet light at their highest frequency.
What color of light is the lowest frequency?
The proton emit a red light at their lowest frequency.
How are electrons “excited”?
Electrons are excited when they absorb energy, such as when they’re being heated in a flame.
What does it mean when the electrons are “excited”?
It means they’re in a higher energy proton shell.
In your own words, write a short explanation of how an electron absorbs energy and re-emits it as light and why different elements have different spectra.
Electrons absorb energy in two different ways. In the first, an electron can be absorb a photon with the precise amount of energy that is needed to move from one quantum shell from another. In the second way is to heat the electrons. When heated, the electrons begin to absorb energy from the heat. When it begins to lose it’s energy, an electron releases a photon of light, a particle of pure energy. The difference between the ground state and the excited energy level with each element, is what causes different elements to have different spectra.
Compound Name | Formula | Flame Color | Observations |
Control (Methanol) | CH4O | Blue, with flashes of Orange | Began as clear liquid; Large Flame Size |
Borax | Na2BuO7 | Green Flame, which tuns into a Yellow Flame | Began as White Powder; Average Flame Size |
Copper Sulfate | CaSO4 | Blue Flame, with flashes of Yellow | Began as Blue Liquid; Small Flame Size |
Magnesium Sulfate | MgSO4 | Blue and Yellow Flame | Began with a White Crystalline Appearance; Large Flame Size; Caused Bubbling |
Strontium Chloride | SrCl2 | Blue Flame, which turns into a Scarlet Flame | Began as a White Powder that Clumped Together; Large Flame Size |
Unknown (Borax) | Na2BuO7 | Green Flame, which turns into a Yellow Flame | Began as Non-Compact Light White Powder; Average Flame Size |
Conclusion
The flame color demonstrates how much energy an element's electrons absorbed, which is demonstrated by it's flame size.
Discussion of Theory
One law that we learned before we began our experiments was that when the compound's electrons had absorbed the highest possible amount of energy, they displayed a violet light. So, since the largest flame had a scarlet color, which is close to violet, I theorized that the large flame size related to the amount of energy absorbed. Most of my other calculations agreed with this: the closer the color was to violet, the bigger it's flame was. The purpose of our experiment was fulfilled, since we were able to see how the different compounds reacted to being set ablaze. In my opinion, the experiment worked, since we managed to get unique reactions from the different compounds when we set them on fire.
Error Analysis
For the fires that weren't noticeably large or small, I merely wrote down that they were of average size after the fact. If I had been more specific and recorded it's size in the moment, I feel like I could have possibly a better conclusion. Also, the control was a liquid, but had a large flame. This may be because the teacher displayed it in a larger watch glass, which was able to contain more of the compound.
Post-Lab Questions
Why do you think the chemicals have to be heated in the flame first before the colored light is emitted?
The element's electrons absorb energy from the heat. Then, when they released the energy, all of the element's electrons emitted photons of light.
Most salts contain a metal and a non-metal. What type of bonds usually form between a metal and a non-metal?
Metals and non-metals typically form ionic bonds.
https://www.princeton.edu/~achaney/tmve/wiki100k/docs/Ionic_bond.html
What is the definition of a salt in chemistry?
"Salts are ionic compounds that can be formed by replacing one or more hydrogen ions acid with another positive ions."*
http://www.chemicool.com/definition/salts.html
*I would have put this in my own words, but the question is asking for exact definition.
What is fire?
Fire is what happens when something undergoing combustion hits an ignition point. When something hits this ignition point it produces flames primarily made out of carbon dioxide, water vapor, oxygen, and nitrogen, which emit heat and light.
http://chemistry.about.com/od/firecombustionchemistry/f/What-Is-Fire-Made-Of.htm
What are the chemicals involved in lighting a match?
The tip of a match is made out of red phosphorus, sulfur, and potassium chlorate, which act as an igniter, a source of fuel, and an oxidizer, respectively. So, when you're lighting a match, the friction causes the phosphorus to ignite, which sets the sulfur on fire and causes the potassium chlorate to release it's oxygen. The oxygen and sulfur are able to keep the flame alive long enough for us to light something like a candle.
http://www.discovery.com/tv-shows/mythbusters/about-this-show/how-matches-work.htm
What is a chemical reaction?
A chemical reaction is when a substance transforms into a new substance with a different chemical identity.
http://www.ric.edu/faculty/ptiskus/reactions/
What natural cycles does wildfire have an impact on?
Fire is a natural cycle of it's own, and since fire can affect all parts of nature, directly or indirectly, wildfires can affect all natural cycles.
http://www.wildcalifornia.org/action-issues/fire/
List at least three impacts of wildfire in San Diego.
Wildfires have damaged stream side vegetation, killed off parts of the deer population, and almost completely destroyed Cuyamaca Rancho State Park.
http://interwork.sdsu.edu/fire/resources/summary_fire_impacts.htm
The flame color demonstrates how much energy an element's electrons absorbed, which is demonstrated by it's flame size.
Discussion of Theory
One law that we learned before we began our experiments was that when the compound's electrons had absorbed the highest possible amount of energy, they displayed a violet light. So, since the largest flame had a scarlet color, which is close to violet, I theorized that the large flame size related to the amount of energy absorbed. Most of my other calculations agreed with this: the closer the color was to violet, the bigger it's flame was. The purpose of our experiment was fulfilled, since we were able to see how the different compounds reacted to being set ablaze. In my opinion, the experiment worked, since we managed to get unique reactions from the different compounds when we set them on fire.
Error Analysis
For the fires that weren't noticeably large or small, I merely wrote down that they were of average size after the fact. If I had been more specific and recorded it's size in the moment, I feel like I could have possibly a better conclusion. Also, the control was a liquid, but had a large flame. This may be because the teacher displayed it in a larger watch glass, which was able to contain more of the compound.
Post-Lab Questions
Why do you think the chemicals have to be heated in the flame first before the colored light is emitted?
The element's electrons absorb energy from the heat. Then, when they released the energy, all of the element's electrons emitted photons of light.
Most salts contain a metal and a non-metal. What type of bonds usually form between a metal and a non-metal?
Metals and non-metals typically form ionic bonds.
https://www.princeton.edu/~achaney/tmve/wiki100k/docs/Ionic_bond.html
What is the definition of a salt in chemistry?
"Salts are ionic compounds that can be formed by replacing one or more hydrogen ions acid with another positive ions."*
http://www.chemicool.com/definition/salts.html
*I would have put this in my own words, but the question is asking for exact definition.
What is fire?
Fire is what happens when something undergoing combustion hits an ignition point. When something hits this ignition point it produces flames primarily made out of carbon dioxide, water vapor, oxygen, and nitrogen, which emit heat and light.
http://chemistry.about.com/od/firecombustionchemistry/f/What-Is-Fire-Made-Of.htm
What are the chemicals involved in lighting a match?
The tip of a match is made out of red phosphorus, sulfur, and potassium chlorate, which act as an igniter, a source of fuel, and an oxidizer, respectively. So, when you're lighting a match, the friction causes the phosphorus to ignite, which sets the sulfur on fire and causes the potassium chlorate to release it's oxygen. The oxygen and sulfur are able to keep the flame alive long enough for us to light something like a candle.
http://www.discovery.com/tv-shows/mythbusters/about-this-show/how-matches-work.htm
What is a chemical reaction?
A chemical reaction is when a substance transforms into a new substance with a different chemical identity.
http://www.ric.edu/faculty/ptiskus/reactions/
What natural cycles does wildfire have an impact on?
Fire is a natural cycle of it's own, and since fire can affect all parts of nature, directly or indirectly, wildfires can affect all natural cycles.
http://www.wildcalifornia.org/action-issues/fire/
List at least three impacts of wildfire in San Diego.
Wildfires have damaged stream side vegetation, killed off parts of the deer population, and almost completely destroyed Cuyamaca Rancho State Park.
http://interwork.sdsu.edu/fire/resources/summary_fire_impacts.htm