Flame Test Lab

FLAME TESTS LAB

Objective: To observe the relationship between various elements and their emission spectrum.

Introduction: Flame tests provide a way to qualitatively test for the presence of specific elements by seeing colored flames.  The heat of the bunsen burner excites the electrons in the atom, and this energy is released as the electrons “fall back” to their ground states. The color we see is a combination of the visible wavelengths of light emitted by the atoms.  

If you have a spectroscope you can also make quantitative observations. A spectroscope can be used to see a pattern of narrow lights called an emission (bright-line) spectrum.  The actually wavelengths of the spectrum serve as a quantitative test to determine atoms identities.  Each element has a different “pattern” of electrons so it will show a different combination of colors.  

In this lab, you will perform flame tests on seven different elements. You will use your observations to identify an unknown solution.  

Prelaboratory Questions:

1, Why do we see colors in the flame tests?

We see colors in the flame tests because of the heat from the flame excites the electrons and causes it to move to another shell, the energy is released once the electrons “fall back” to their ground state. The color we see is a combination of a visible wavelength that produces the visible light that we see. Each element has a different “pattern” of electrons. So the color combination may be different.

2, How will we be testing the substances qualitatively?

We will be testing the substances qualitatively by observing the flame colors.

Materials: Safety goggles, wood splints, tongs/tweezers, Bunsen burner, test tubes with various compounds

Safety:

1, Safety goggles must be worn at all time

2, Many of these salts are toxic. If you come into contact with any of the compounds make sure to notify the teacher and wash the contacted area thoroughly. Wash your hands before leaving the lab!

Procedure:

1, Light the Bunsen burner (turn the gas on so you can just hear it, then use the striker)

2, Place the wood splint for each compound into the flame using tongs or tweezers- ONE AT A TIME!

3, Take note of the color of the flame and return the wood splint to the solution.

4, CLEAN UP YOUR STATION! Carefully put the stoppers back on the solutions! Make sure the station looks like it did when you started! Let me know if you need new splints!

5, Wash your hands thoroughly before leaving the laboratory

Data Table: make a section of your lab labeled Data Table and make a data table similar to the one below to record your observations.

Compound The color of Flame (qualitative) Wavelengths of light (in Å) (quantitative)
Barium Chloride Orange 5900 – 6200A
Calcium Chloride Red 6200 – 7500A
Copper (II) Chloride Green 4950 – 5700A
Lithium Chloride Violet 3800 – 4500A
Potassium Chloride Orange 5900 – 6200A
Strontium Chloride Red 6200 – 7500A
     

Discussion and Analysis: (In a section labeled Discussion and Analysis answer the following questions in complete sentences)

1, How do your results from the flame test provide support for quantized energy levels? Explain your answer.

By heating the compound, the electrons got excited and jump to a higher energy. At the electrons “fall back” to their ground state, they emit energy  (photon). The different element has a different pattern of electrons, therefore it has a different energy level. While releasing the energy, they also produce visible light as a result of a combination of visible wavelengths. This allows us to see the colors of the flame (qualitative data). The result collected from the flame test provide support for quantized energy levels as it provides the color for different compound and allowed us to look up the wavelength of different light color.

 

 

 

របៀបតែងបទពាក្យប្រាំពីរ

បទពាក្យ៧

ក. រង្វាស់កាព្យ​ : 

ក្នុង១វគ្គ មាន៤ឃ្លា ក្នុង១ឃ្លាមាន ៧ព្យាង្គ្គ​ ។

ខ. ចួនក្នុងវគ្គ : 

ព្យាង្គ្គទី៧ នៃឃ្លាទី១​ ចួននឹងព្យាង្គ្គទី២ ឬព្យាង្គ្គទី៤ នៃឃ្លាទី២ ។

ព្យាង្គ្គទី៧ នៃឃ្លាទី២ ចួននឹងព្យាង្គ្គទី៧ នៃឃ្លាទី៣ ហើយចួននឹងព្យាង្គ្គទី២ ឬព្យាង្គ្គទី៤ នៃឃ្លាទី៤ ។

គ. ចួនឆ្លងវគ្គ: 

ព្យាង្គ្គទី៧ នៃឃ្លាទី៤ ក្នុងវគ្គមុន ចួននឹងព្យាង្គ្គទី៧ នៃឃ្លាទី២ ក្នុងវគ្គបន្ទាប់ ។

ឃ. កំណត់សម្គាល់: 

បើសិនជាកំណាព្យចួន​នឹងឃ្លាទី២ រាល់វគ្គក្នុងកំណាព្យត្រូវចួននឹងឃ្លាទី២ ។ ហើយបើសិនជា កំណាព្យចួននឹងឃ្លាទី៤ រាល់វគ្គក្នុងកំណាព្យត្រូវចួននឹងឃ្លាទី៤

ឧទាហរណ៍: 

(និពន្ធដោយ ឈឺន ឈឿ)

ចួនក្នុងវគ្គ

ព្យាង្គ្គទី៧ នៃឃ្លាទី១ ក្នុងវគ្គទី១  ​​ ជួននឹង ព្យាង្គគ្គទី៤ នៃឃ្លាទី២ ក្នុងវគ្គទី១ ។

ព្យាង្គ្គទី៧ នៃឃ្លាទី២ ក្នុងវគ្គទី១   ជួននឹងព្យាង្គទី៧ នៃឃ្លាទី៣ ក្នុងវគ្គទី១ ហើយជួននឹង

ព្យាង្គទី៤ នៃឃ្លាទី៤ ក្នុងវគ្គទី១ ។

ចួនឆ្លងវគ្គ

ព្យាង្គ្គទី៧ នៃឃ្លាទី៤ ក្នុងវគ្គទី១   ជួននឹងព្យាង្គទី៧ នៃឃ្លាទី២ ក្នុងវគ្គទី២ ។

Speech and Debate

Aside from picking a topic and debate for an hour, we redirect our focus on strategies used in speaking or even the voices that are stated in pictures. That includes formal speeches, presentation, posters or flyers in the advertisement. In other words, we learned about rhetorical appeals. There are three which are Ethos,  Pathos, and Logos. Ethos is about how you convince an audience of your credibility. Pathos appeals to emotion which could sometimes be irrational and unpredictable  Logos is the use of logic and reason, using factual knowledge to convince the audience.  For example, analogy, examples, citations of research or statistics. After trying to comprehend these three rhetorical appeals, we took it to another level by applying one of these three when giving a one-minute speech. You are given three words. Then you need to make connections between the three words and give a persuasive speech using one of the three appeals. It’s very useful to take a closer look at the art of persuasion because, in our daily life, we apply these strategies in our speech without even noticing it. 

Solar Pi Grant Writing

In order to get funds to implement the Solar Pi project in two pilot schools, a grant proposal was required. This money is to support the Solar Pi Exploration Round 2, which I am not a part of.

Summary of Solar Pi Exploration: Implement Solar Pi into two government schools to test out the program. If it works well within these two schools, the program can be expanded in a wider range Cambodia. Solar Pi runs by using the converted energy from the sun; it has a long-term durability. In countries like Cambodia, it’ll be an advantage because of the vast amount of sunlight. By using Solar Pi, little to no money is required, unlike electricity. We can install offline applications including English and 3D program that students can self-teach during free time. This will raise their proficiency to the highest levels before graduating from high school which will further be beneficial for the students and Cambodia. 

However, without the money, the project won’t process. The grant is strenuous. You have to understand most parts of the project, have every little piece of information, brainstorm an outline for the grant, and finally, fill out all the sections of the grant. Furthermore, persuasive language is necessary. It was really quite a challenge because it was my first time. Lastly, the grant was finalized and sent out and hopefully, it’ll be accepted! 

Pchum Ben

During Khmer class, we were working on writing a report about a ceremony called Pchum Ben. Pchum Ben is a ceremony that dedicates those the spirits that we believe are in hell. People believe that during this ceremony, in a period of 15 days, those spirits are freed from hell to get food from their family. So, we wrote a report about the celebration of the ceremony, apparels to go to the pagoda and the history about this event.

Coming of Age Narrative Essay

In English literacy, we have done one main project which is a narrative essay about coming of age. It took us a few weeks to brainstorm, write, revise and finalize. At first, we brainstorm the moment that we feel important in our life, a moment that we feel more mature, the coming of age moment. Second, we try to write up to two to three pages. Then, we revise both grammatical errors and the context, to ensure that it makes sense. Next, we edit with a partner. Lastly, we evaluate ourselves with a rubric. In doing this process, we also learn about parallel sentences and concision.

Basketball

Basketball is an after school extension. I join basketball because I feel like in basketball, you really need to collaborate and understand the strategies. Compared to other sports, you have little to no time to hesitate when playing basketball. You have to think and react swiftly. I find it hard to play, shoot and dribble, but I still entertain it very much.

Bambujaya

A new school called “Bambujaya” is opening up and needed to hire curriculum developers to rewrite all the Khmer grade one textbooks, Khmer Literacy, Math and Science and Social Studies. The modifications made were mostly due to gender equity and stereotypes, words that aren’t commonly used, and images that look harmful or aren’t associated with Cambodia. Since photo enhancement is necessary in order to rewrite the textbooks, we have recruited some Liger students to illustrate pictures and take photos for us with a clear written contract. With two weeks left, instead of continuing to revise the textbooks, we have chosen main content (chapter) from each textbook and adding activities to it. Then, we convert all the ideas we brainstormed into Prezi presentations. The Exploration ended, but it continues into an Expertise because we need to keep improving and finalize the product.

Advanced Placement Computer Science (AP Com Sci)

Advanced Placement Computer Science (AP CS) is a course of programming. In this class, we learn how to code with Java. These first several weeks, we learned how to use basic calculations, learned about primitive types and non-primitive types of data and studied the foundations. The class is a preparation for the AP Stats exam in February.

Friction Lab

Physic is a quite hard subject to comprehend because there aren’t a lot of real examples to represent the equations. One of the things we did in class was a lab experiment. Using tape, and different sandpapers on a wooden ramp, we tried to find the coefficient of friction to make the object moves.
Picture of the activity is being sent…