Name: _____________________________________________ Date: ______________________ Period: ________
Flame Test Experiment: Atomic Emissions
Purpose:
Upon completion of this experiment, students will be able to list the flame color of several different metals. They
will be also be able to calculate the energy involved in the movement of electrons in the metals.
Background / Introduction:
When atoms or ions in the ground state are heated to high temperatures, some
electrons may absorb enough energy to allow them to “jump” to higher energy
levels. These excited state electrons are unstable and they will “fall” back to
their normal positions of lower energy. As the electrons return to the ground
state, the energy that was absorbed is emitted in the form of electromagnetic
energy. Some of this energy may be in the form of visible light (colors). The
color may be described in terms of its wavelength, and the following equation
may be used to calculate the energy of the emitted photon:
∆𝐸 =
ℎ𝑐
𝜆
∆E is the difference in energy between the two energy levels in joules (J), h is Planck’s constant (6.626x10 -34 J*sec),
c is the speed of light (3.0x108 m/sec), and λ is the wavelength of light in meters. The wavelengths are typically
given in units of nanometers, nm, (1 meter = 1,000,000,000 nanometers).
Each metal has its own specific color due to the amount of electrons and where they are spaced in the atom. Flame
colors and the energy changes are used to help in identifying unknown substances, a qualitative analysis technique.
The visible portion of the electromagnetic spectrum ranges from about 400 to 700 nm. The table below shows the
approximate values for each observable color.
Procedure:
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Record the compound name from the board.
Each solution is set up at tables along with a burner. Move from one table to another making sure that you
DO NOT CHANGE ANY OF THE WIRES FOR EACH SOLUTION!!
Clean the wire for the solution by placing it in the flame until no color is seen.
Dip the cleaned wire into the solution and place the tip of the wire into the flame, noting the color of the
flame. Record this color and solution.
Clean the wire and place it back down at each station.
Based on the color of light emitted, record the corresponding wavelength listed in the provided table.
Calculate the frequency and energy of light emitted using our equations from class.
Repeat the steps for each of the supplied solution.
Materials, Safety Information, etc. should be included as you go in this lab 
Color
Violet
Blue
Green
Yellow
Orange
Red
Wavelength of Light λ
(m)
4.20 x 10-7
4.75 x 10-7
5.40 x 10-7
5.80 x 10-7
6.05 x 10-7
6.35 x 10-7
Given Information / Equations:
c = λν
c = 3.0x108 m/s
λ  wavelength ν  frequency
∆E = hν
∆E  Energy
h = “Planck’s Constant”
Compound
Color of Light
Wavelength of Light, λ
(m)
Frequency of Light, ν
(Hz)
Energy, E
(J)
1
2
3
4
Data Analysis: Electron Configuration
1.
The metal in compound 1 is __________________________________________.
Write the electron configuration for the metal
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2.
The metal in compound 2 is __________________________________________.
Write the electron configuration for the metal
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3.
The metal in compound 3 is __________________________________________.
Write the electron configuration for the metal
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4.
The metal in compound 4 is __________________________________________.
Write the electron configuration for the metal
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Post Lab Question:
1.
Reflecting on the atomic emission spectroscopy lab and this demonstration, what is occurring at the atomic
level that causes visible light to be emitted when energy is applied?
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