This will help you to formulate a hypothesis based within the context of knowledge you already possess. Go back to the bicycle mentioned in the first sentence of this section. Under what type of circumstances did your bike rust? When it was stored in the dry garage? Or when you left it lying out in the yard for three days during a steady rain? Why do you suppose that cold-weather drivers are advised to rinse off their cars every now and then during the winter season when road salts are being used?
Have you ever noticed or heard people talk about problems with corrosion near the beach, where salt water is prevalent? Do you already know, perhaps, which metals are most resistant to corrosion? If so, the experiment you'll do will support and affirm your knowledge. If you don't, try to use common sense and any information you may have about this topic to come up with your best guess-or hypothesis.
The experiment you'll be doing will require only a short amount of time to set up, but you'll need to make observations over a day period. It's going to be important to write down exactly what you see happening to each metal each day. Remember that your measurements will be qualitative, not quantitative. For that reason, the more data you present concerning your experiment, the more reliable your results will be. You'll need some materials for this experiment that probably aren't lying around your house.
You should be able to find everything you need, however, at your local hardware or home supply store. You will need:. If you can get test tubes and a rack, you'll probably find them easier to use than glasses. If you have to use glasses, however, that's fine. You can use plastic or glass cups; just make sure that they're clear so you're able to easily observe what's happening to the wires in them.
Make sure that you have all your materials ready before you begin the experiment. Be sure to find an area large enough to accommodate the glasses or test tubes, where they will be undisturbed for the duration of your experiment. Remember that the more clear and accurate your observations are, the better you'll be able to draw conclusions from your experiment.
Use the charts on the following section, or make your own, similar charts to keep track of what you observe during the course of your experiment. Be sure to not mix up the glasses. They'll all look very similar, so be sure that the labels remain intact and you can see them clearly. Some observations you'll want to consider are how the changes to the metal wires immersed in the distilled water compared to the wires in the salt water.
Which metals had the most rust? Was the formation of the rust on any of the wires concentrated on one particular area on the wire? Or was the corrosion distributed evenly along the immersed wire? Based on your data, which metal would you recommend for the manufacture of bikes, beach chairs, and swing sets-not to mention aircraft and medical equipment? Once you've recorded your results, you can draw a conclusion and identify the answer to the problem you stated at the beginning of your project.
If you enjoyed this project and would like to take it a step or two further, you could try one of the following ideas:. Use your imagination to come up with other ways to vary the project and delve a bit further into this issue.
Just be sure to keep good, accurate notes. Students test a variety of metals in water and salt water to determine which corrodes the fastest with this hands-on printable science activity. Check out our collection of hands-on projects that combine math, ELA, and science concepts with 21st Century and social-emotional skills! Manage My Favorites. Log in or use the form below to start receiving updates. We usually think of rust as the orange-brown flakes that form on an exposed steel surface when iron molecules in the metal react with oxygen in the presence of water to produce iron oxides.
Metals may also react in the presence of acids or harsh industrial chemicals. If nothing stops the corrosion, flakes of rust will continue to break off, exposing the metal to further corrosion until it disintegrates. Not all metals contain iron, but they can corrode or tarnish in other oxidizing reactions. Stainless steel types, such as or , are a mix of elements, and most contain some amount of iron, which easily oxidizes to form rust.
But many stainless steel alloys also contain a high percentage of chromium — at least 18 percent — which is even more reactive than iron. The chromium oxidizes quickly to form a protective layer of chromium oxide on the metal surface.
This oxide layer resists corrosion, while at the same time prevents oxygen from reaching the underlying steel. Other elements in the alloy, such as nickel and molybdenum, add to its rust-resistance.
Many aircraft are made from aluminum , as are car and bike parts. This is due to its light weight, but also to its resistance to corrosion. The rusting rate may be the same, but you may notice it sooner in thin metal sheeting than on a thick piece of iron because the former will have a hole in it sooner. Some kinds of steel wool also rust quickly they are commonly exposed to water so this doesn't help , although other steel wools are made of stainless steel or coated.
If you have two different metals in electrical contact, and both in contact with salty water, then effectively a battery is made. Current flows, and the energy comes from the corrosion of the metals. Some companies sell blocks of zinc that you can attach to boats so that the zinc corrodes first, protecting the other metals. Vinegar and bleach have been tried and seem to affect the rusting rate. Fresh iron exposed to a hot atmosphere with plenty of oxygen and water will form a thin layer of rust immediately although if you look at a very short time after exposing the iron surface, you will have a very small amount of rust.
Any of the above variables can affect the rusting rate however. Can you think of more? I read what Tom said about the rate of rusting and stainless steel does rust!
I did an experiment on rusting stainless steel and it rusted in water, salt water, vinegar, lemonade and red cordial. Beth, thanks. The rate of stainless steel rusting is very sensitive to what type of stainless it is.
The amounts of chromium, nickel etc. When a 'stainless' steel has pockets of nearly pure iron, it will rust. Mike W. I just wanted to add that contact with other metals will contaminate the Stainless at almost any grade.
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