Connection: Iron Oxide Lab
- mean, median, mode, range,
line graphs, data tables
- creating a compound produces
Sunshine State Standards:
Materials per lab group:
The following materials are enough for groups of 4
4 data tables
1 piece of chart paper with the experiment procedure listed on it (see
1 large jar with lid (a deli
pickle jar works well.)
1 piece of masking tape approximately
6 inches long. (If you have enough rolls, just give one roll to each
1 rectangular piece of steel
wool (no soap) about 1.5 inches x 2 inches
1-2 paper towels
1 rubber band
1 small container filled with
enough vinegar to cover the steel wool
4 pairs of goggles
1 watch (a class wall clock
4 calculators (if necessary)
The children should be placed
in groups of 3 or 4 for this activity.
Note: This lab should be
done following preliminary work on atoms, molecules, and formulas.
and discuss the parts of a compound.
- Discuss that the purpose
of this lab is to learn what happens when a chemical change creates
- Donít tell the students
that the common name for the compound iron oxide is rust. Let them figure
that out for themselves.
- Introduce the children to
the materials in their lab baskets.
- Show them each item and
demonstrate the proper set up for their lab.
- Have a chart available for
them to read to help simplify the procedure.
- This is good time to discuss
constants and variables.
- Hand out a copy of their
data table. (If the
students donít have experience with this this type of data collection,
then make sure that they understand that they should only write their
data on the chart as they collect it. They will fill in the rest of
the classís data later.)
- Have students begin the
lab by following the directions on the chart:
- Record the beginning
temperature from your thermometer on your data chart.
- Put on goggles.
- Place steel wool in
vinegar for 30 seconds. Squeeze until it doesnít drip.
- Wrap steel wool around
the bottom of the thermometer. Attach it by wrapping a rubber band
- Place tape on the thermometer
and hang it inside the jar SO THAT YOU CAN READ IT FROM THE OUTSIDE.
- Close the lid and do
not open it again until you are instructed to do so.
- Take off goggles.
- Record temperature every
2 minutes. Record any changes seen in the jar on the back of
your data chart.
- When each group has recorded
their data for 14 minutes, instruct them to open the jar. They should
smell the inside of the jar and feel the moisture in the jar.
- Now is a good time to discuss
the reaction that took place. Iron oxide is formed when iron and oxygen
mix in the presence of water. How did this happen? The creation of rust
happens slowly. It happened quickly in this lab because the acid in
the vinegar removed the protective coating that may have been on the
steel wool. That paved the way for the iron that is in the steel wool
to rust because it was in the presence of water from the vinegar. This
chemical reaction produced heat which was evident from the increase
in temperature on the thermometer.
- Have students clean up their
lab area and prepare to copy the rest of the classís data.
- Have each lab group share
their data so that everyone can place the information on their individual
data sheets. Having a large class data chart is very helpful for this
type of activity.
- When all the data is recorded,
then find the mean, median, mode, and range for each column. Students
can do this in a variety of ways. You may want to have each lab group
do one column, or you may want to do each calculation as a whole class.
Calculators are helpful for this activity.
- Following the completion
of the data charts, create a line graph that will show the temperature
over a period of time.
- Discuss the title, horizontal
axis and vertical axis, appropriate scale, etc.
- Now itís time to draw conclusions.
The line should show a rapid increase, may stay the same for a short
period of time, and then finally start to decrease.
- The class can make predictions
about the temperature in the jar at certain periods of time. Will the
temperature ever decrease to zero? Why? What will the line look like
after 30 minutes?
- You may want to give children
a worksheet to do as a conclusion or have them write a conclusion that
answers several questions related to the lab. One of the questions should
pertain to the fact that chemical reactions produce heat. Some of the
other questions should address the increase and decreases that are seen
on the graph.