Electrons and Quantum Mechanics - Oakland Schools

Name ______________________________ Date ____________ Class _________
Investigation s becomes before d
Student Sheet
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.
Materials
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
Goggles must be worn during this experiment; 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.
Procedure
1. Into the first large test tube, place approximately 2 g of iron filings. Add 4 ml of
water to the test tube, followed by 4 ml of concentrated HCl. Record your
observations.
2. Into a second large test tube, place approximately 2 g of iron (III) chloride,
FeCl 3 . Add 8 ml of water to the test tube. Place a rubber stopper into the test
tube and shake until some of the compound has dissolved. Record your
observations.
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