Transcript Technicolor Atoms

Technicolor Atoms
The Flame Tests
Pre-Lab
• Read the lab description on page 86.
• Make a data table with the headings
below:
• List the substances and their formulas in
the table from the materials list on pg 86.
Chem Catalyst
• These drawings are models that show solid
copper, solid copper chloride, and aqueous
copper chloride as collections of atoms.
1. Describe each model.
2. What is similar about each model? What
is different?
Safety
• Legs and feet covered
• Hair tied up
• Move with caution
• Monitor bunsen burners carefully
• Do not cross-contaminate Q-Tips
Go Do Lab
Team Analysis
1. Group the substances based on the flame
colors produced.
2. What patterns do you notice in the
groupings?
3. Predict the flame color for a substance
called strontium sulfate. Explain your
reasoning.
4. What evidence do you have that atoms of
certain elements produce a flame of a
specific color?
5. Can a flame test be used to identify a metal
atom in a compound? What about a
nonmetal atom? Explain.
Discussion
• Which part of the compound seems to be
producing the colors? What’s the evidence?
• How can you use the flame test to identify
elements in a substance?
• What are some good uses for this
phenomenon?
Notes
• It is the metal in the compounds which
causes the colored flame
• The flame test can be used to
determine what metals in are in an
unknown compound.
• Metals are used in fireworks and other
applications for color
More Notes: Explaining the Colored Light
• Electrons can move within
the atom.
• Heat from the flame
excites the electrons,
causing them to jump to
an energy level farther
from the nucleus.
• When the electrons “fall”
back to their original
energy level, energy is
released as colored light.
Sodium Atom
The different colors of light released
are evidence that electrons move in
different “energy shells”.
Getting Specific
• If you pass the colored
light through a prism or a
diffraction grating, the
color will get separated
into specific wavelengths
of light. This is an
emission spectrum
• All elements have an
emission spectrum, and it
is unique to that element
– like a finger print.
Homework
• Lesson 17
• Read pages 87-90
• Questions 1-2, 5-7,
9-11