We’ve all watched something rust. Not very exciting and it takes a long time. But what would happen if you could make something rust very quickly? In this experiment you will see what really happens when something rusts. It is actually quite fun, really!
Student Guide
Rusted Out
An experiment to explore rusting metals.
What happens when an object rusts?
This resource was originally published in PhysicsQuest 2011: Spectra Heats Up!
What happens when an object rusts?
- Packets of vinegar
- Steel wool
- Clear plastic bag
- Liquid crystal thermometer
- Cup
- Paper towels
- Stopwatch or watch with a second hand
Intro
Before the experiment
Have you ever seen things rust? What does it look like?
- Sketch a rusting object.
Predict three things that you will see when you watch something rust quickly.
What things do you think can make something rust faster?
Setting Up
Open the zip lock bag.
Stick the liquid crystal thermometer to the inside of the bag so that you can see it through the bag. (Figure 1)
Figure 1Pour all the vinegar packets into a cup.
During the experiment
Place the steel wool in the vinegar and make sure it is completely covered in vinegar.
Let the steel wool soak in the vinegar for 5 minutes
Pull the steel wool from the cup and very quickly blot the vinegar off with the paper towel then quickly place it in the bag and seal the bag. (Figure 2)
Figure 2Record the temperature on the thermometer every 3 seconds.
- Make sure you also have a hand on the bag so that you can feel the temperature change.
Analyzing data
What were your results?
- How did the appearance of the steel wool change?
- What other changes happened?
- What happened to the temperature of the steel wool?
Why did you need to soak the steel wool in vinegar?
Make a graph of temperature vs. time
Conclusions
What changes happen when something rusts?
Look back at your predictions. How does what you saw compare with what you thought you would see?
Write a claim about the relationship between temperature over time as something rusts.