COPY: Experiment 3: Flame Test and Atomic Spectra

This lab will be a little different than prior labs. You will be completing the lab virtually. You will still complete the lab in your lab notebook (to ensure that you have record of the lab) like you have before, but you will be answering all of the lab questions here. 

Here is how you will complete the lab: 

Read the background information below (or in the lab handout here: https://docs.google.com/document/d/10Me2VnpmUpWEfBoFQ8nat2Cus6Da7sPcLhx0-gScCMA/edit?usp=sharing). In the background information you will find the purpose. Record the purpose of the lab in your lab notebook. 

Complete the rest of your pre-lab in your lab notebook (procedure for both days and pre-lab questions). 

After you complete the pre-lab questions in your lab notebook, answer the questions here to recieve credit. 

Watch Part 1 of the lab. As you watch the video, record your data & observations in a data table in your lab notebook. (This will be in your data & observations section of your notebook.)

Complete Part 2 of the lab. This will require you to observe pictures of gas discharge tubes and the corresponding emission spectrum. Fill in your data table in your lab notebook. Again remember to label your each data table appropriately and use a ruler or straight-edge. 

Work through the post lab questions for both part 1 and part 2. Answer the post lab questions in your lab notebook and then answer certain questions here to receive credit. 

Finally, write your conclusion (purpose, was it fulfilled, why or why not) in your lab notebook. Then transfer it here to receive credit. 

As you work through the lab, send any questions through email or Remind.

0

Read the background information to review light and waves, as well as to find the purpose of the lab. Check below once you've read it.

3

Calculate the corresponding wavelength (in m), frequency (in Hz), and energy (in J) associated with each line in the table. Match the appropriate value with each label.2

Remember to fill in the table in your pre-lab as you complete the prelab. Show work in your lab notebook for one of each calculation.

Draggable item		Corresponding Item
6.91E14		Red wavelength (m)
6.56E-7		Red Frequency (Hz)
4.34E-7		Red Energy (J)
7.31E14		Blue-green Wavelength (m)
4.86E-7		Blue-green Frequency (Hz)
4.10E-7		Blue-green Energy (J)
4.09E-19		Blue Wavelength (m)
4.84E-19		Blue Frequency (Hz)
3.03E-19		Blue Energy (J)
6.17E14		Violet Wavelength (m)
4.58E-19		Violet Frequency (Hz)
4.57E14		Violet Energy (J)

0.5

Calculate the energy of this photon (in J). Give your answer to 3 SF.
Only include the number. You can use the format 3E-10 or

0.5

Convert this energy to kJ/mol.
Only give the numeric answer.

0.5

The ionization energy of sodium is 496 kJ/mol. Would light with a wavelength of 400 nm be sufficient to cause sodium to lose its electrons? Explain why/why not.
(Hint: You just calculated the energy in kJ/mol for 400 nm light.)

0.5

Calculate the minimum wavelength of light (in nm) that would be needed to cause a single sodium atom to lose an electron.
Give only the numeric portion of the answer.

Read the procedure for Part 1 and record the procedure in your lab notebook (as you would for any pre-lab). Watch the flame test video below, recording all data in the data table. We did not examine the Sodium/Potassium combo or the unknown, so you do not need to record those in your lab notebook. 

3

Be sure to copy the data table in your lab notebook (and give it an appropriate number and title).

Match the correct colors to metal ions.

Draggable item		Corresponding Item
Yellow-green		Copper
Yellow		Barium
Orange		Lithium
Bright red		Calcium
Lavender		Sodium
Blue-green		Potassium

1

List the colors of visible light from highest energy to lowest energy.

Green
Yellow
Red
Orange
Blue
Violet

1

List the colors of visible light from highest frequency to lowest frequency.

Orange
Blue
Red
Violet
Green
Yellow

1

List the colors of visible light from shortest wavelength to longest wavelength.

Yellow
Green
Orange
Blue
Violet
Red

Answer questions 4 & 6 in your lab notebook. You can skip #5 because we did not test an unknown. 

1

How are the electrons excited during flame tests?

1

What particles are responsible for the production of light?

1

Why do different chemicals emit different colors of light?

Answer #10 & 11 in your lab notebook. 

4

Be sure to copy the data table in your lab notebook (and give it an appropriate number and title).

Match the color of discharge tube and number of lines to the correct element/compound.

Draggable item		Corresponding Item
		Hydrogen
		Helium
		Neon
		Argon
		Bromine
		Water vapor
		Carbon Dioxide
		Mercury

As you work through the part 2 post lab questions (answering in your lab notebook as well), remember that the background provides lots of information that will be useful for these questions. 

2

Categorize the definitions/examples to the correct type of spectrum.

Neon Signs
Dark lines on colored background
Bright lines on dark background
Rainbow
Thermal spectrum

Line Spectrum
Continuous Spectrum

2

Each line in the emission spectra of hydrogen corresponds to an electromagnetic radiation with a specific wavelength.
Match the four observed colors with the correct wavelengths.

Draggable item		Corresponding Item
Red		410 nm
Green		434 nm
Blue		486 nm
Purple		656 nm

1

How are electrons excited in this part of the lab?

Answer #4 in your lab notebook. Remember to reference the backgroun information and your notes to help you with this question! 

2

It has been calculated that the observed colors in a hydrogen atom correspond to the relaxation of the electron from a higher energy level to the second energy level.
Match the correct color to energy transition (think about how you know which color correponds to the transition).

Draggable item		Corresponding Item
Blue
Red
Green
Purple

Answer #6-8 in your lab notebook. 

Add your conclusion to your lab notebook. Remember that you need to reference both parts 1 & 2. 

2

Read the background information to review light and waves, as well as to find the purpose of the lab. Check below once you've read it.

Calculate the energy of this photon (in J). Give your answer to 3 SF. Only include the number. You can use the format 3E-10 or

Convert this energy to kJ/mol. Only give the numeric answer.

The ionization energy of sodium is 496 kJ/mol. Would light with a wavelength of 400 nm be sufficient to cause sodium to lose its electrons? Explain why/why not. (Hint: You just calculated the energy in kJ/mol for 400 nm light.)

Calculate the minimum wavelength of light (in nm) that would be needed to cause a single sodium atom to lose an electron. Give only the numeric portion of the answer.

Be sure to copy the data table in your lab notebook (and give it an appropriate number and title). Match the correct colors to metal ions.

List the colors of visible light from highest energy to lowest energy.

List the colors of visible light from highest frequency to lowest frequency.

List the colors of visible light from shortest wavelength to longest wavelength.

How are the electrons excited during flame tests?

What particles are responsible for the production of light?

Why do different chemicals emit different colors of light?

Be sure to copy the data table in your lab notebook (and give it an appropriate number and title).Match the color of discharge tube and number of lines to the correct element/compound.

Categorize the definitions/examples to the correct type of spectrum.

Each line in the emission spectra of hydrogen corresponds to an electromagnetic radiation with a specific wavelength. Match the four observed colors with the correct wavelengths.

How are electrons excited in this part of the lab?

It has been calculated that the observed colors in a hydrogen atom correspond to the relaxation of the electron from a higher energy level to the second energy level.Match the correct color to energy transition (think about how you know which color correponds to the transition).

Write your conclusion below. Reference both parts 1 & 2.

Calculate the energy of this photon (in J). Give your answer to 3 SF.
Only include the number. You can use the format 3E-10 or

Convert this energy to kJ/mol.
Only give the numeric answer.

The ionization energy of sodium is 496 kJ/mol. Would light with a wavelength of 400 nm be sufficient to cause sodium to lose its electrons? Explain why/why not.
(Hint: You just calculated the energy in kJ/mol for 400 nm light.)

Calculate the minimum wavelength of light (in nm) that would be needed to cause a single sodium atom to lose an electron.
Give only the numeric portion of the answer.

Be sure to copy the data table in your lab notebook (and give it an appropriate number and title).

Match the correct colors to metal ions.

Be sure to copy the data table in your lab notebook (and give it an appropriate number and title).

Match the color of discharge tube and number of lines to the correct element/compound.

Each line in the emission spectra of hydrogen corresponds to an electromagnetic radiation with a specific wavelength.
Match the four observed colors with the correct wavelengths.

It has been calculated that the observed colors in a hydrogen atom correspond to the relaxation of the electron from a higher energy level to the second energy level.
Match the correct color to energy transition (think about how you know which color correponds to the transition).