Peter Jeschofnig, Ph.D. Version 42-0160-00-01
Lab Report Assistant
This document is not meant to be a substitute for a formal laboratory report. The Lab Report Assistant is simply a summary of the experiment’s questions, diagrams if needed, and data tables that should be addressed in a formal lab report. The intent is to facilitate students’ writing of lab reports by providing this information in an editable file which can be sent to an instructor.
The color of the flame is expected to be as follows:
Metallic ion Flame color
Sodium Na+ Strontium Sr2+ Potassium K+ Lead Pb2+ Barium Ba2+ Copper Cu2+ Lithium Li+ Calcium Ca2+ Unknown
A. All chemical used in this test are binary compounds. What portion of the periodic table is responsible for the color observed?
B. In cooking over an open flame, a yellow flame is often observed when some food is spilled into the flame? What is most likely responsible for the yellow flame color?
C. What problems might be associated with using flame color for identification purposes?
D. Explain how the observed colors are produced
The normal configuration of the electrons about the atom or the ion of an element is called
“the ground state.” The electrons of this stable particle are at their lowest possible energy level.
However, when these stable particles are heated to very high temperatures some of the electrons leave their ground state and become “excited”; that is, these electrons move to higher energy levels. They do so by absorbing heat energy. This “excited” state is quite unstable