Electrons and Quantum Mechanics - Oakland Schools

Electrons & Quantum Mechanics
Activity #4 – Investigation s becomes before d
Questions to be investigated
How is it possible for a transition metal to have more than one oxidations state?
If you have the two of the same transition elements with different oxidation states,
which oxidation state is more stable?
Objectives
Students will observe two forms of ions.
Students will describe the relationship between electron configuration and oxidation
number for these two ions.
Teacher Notes
DISPOSAL: Collect and recycle the FeCl 3 by reusing it in the laboratory. Mix the HCl
with water and a large amount of Na 2 CO 3 and Ca(OH) 2 . When neutralized flush down
the drain with a large amount of water.
Materials
Each group of students need:
2 large test tubes
test tube rack
2 g iron filings or steel wool
2 g iron (III) chloride, FeCl 3
4 ml concentrated HCl
12 ml distilled water
2 rubber stoppers (fit into test tubes)
balance
graduated cylinder
goggles (each student)
aprons
Safety Concerns
Goggles are needed for every student; aprons if available.
CAUTION: Always add acid to water. Concentrated HCl causes severe burns; avoid
skin contact. Rinse spills with plenty of water. Dispose of all chemicals as instructed
above.
CAUTION: FeCl 3 is a skin irritant.
Sources
Smoot, Robert C., and Richard G. Smith. Chemistry A Modern Course Teacher Resource
Book. Columbus OH: Merrill, 1987.
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