riment is complete.
If he learns to clearly differentiate between what he has actually observed vs. people's theories for why it happened, the project has been a huge success. If he learns to fudge his observations just a little bit so it's easier to arrive at the popular conclusions, the project was a disaster. Best of luck!
Ted Mooney, P.E. RET
Brick, New Jersey
August 2, 2009
I have recently done the same sort of thing.
I had to conduct an experiment which explored whether acids or bases had a larger effect on metals. I decided to conduct an experiment that tested corrosion.
I used un-galvanised steel, a very simple and cheap product. (I purchased small corrugated pieces in a packet from the hardware store).
The acids and bases that I used were simple household ones such as acids- vinegar, lemon juice. and bases- ammonia and shampoo.
This experiment, although simple as it is, provided excellent results that I was able to assess and discuss very successfully. It was also very cost-efficient and could be conducted in my own time because it wasn't dangerous. All of the materials were so easily accessed.
Household acids have a high corrosive affect on metals!
- Sydney, Australia
opinion! April 16, 2011
I stumbled across this page because I'm doing some research on dissolving powder coatings on metals without destroying the integrity of the substructure. The postings didn't really apply to my situation but I figured I would add my two cents to the subject. Ted, I agree with everything you have said and it is all completely true in my eyes. I graduated a couple years ago with a BS in Mechanical Engineering so I have had a decent amount of schooling. Learned a lot of great things, learned a lot of useless trivia, also forgot a lot.
I recently tried to soak a wheel in muriatic acid to dissolve the existing powder coating. Found out that I had committed a huge brain fart when I pulled the HOT wheel out of my smoking tub of acid. Completely forgot about how acids affects metal, especially strong acids like hydrochloric.
One experiment that has fascinated me ever since I saw it, was the separation of hydrogen and oxygen (electrolysis of water). It was done by the teacher my freshman year in high school because it was considered 'dangerous'. It wasn't dangerous, it was inspiring. I didn't learn testing procedure or how to list my observations correctly, what I learned was how to extract hydrogen and it stuck with me ever since. I agree that process and procedure is important to learn but they should be learned with experiments. Experiments are done because the end result is unknown and if that's what you are trying to do then you need to listen to everything Ted has mentioned above. If you are not testing for the unknown but instead demonstrating the awesome power of science then maybe a different approach should be considered. Seems like these postings were related to younger kids in elementary school. Kids in elementary school don't give a rats a** about proper procedure, they want to see cool things happen. Teachers should be spending their time and efforts trying to capture young minds and teach them science. Science has been around for a long time. There's no need to continuously derive how F=ma -- Newton did it a long time ago and it makes sense. Lets go with it. There's plenty of time to teach kids proper procedure in high school and college when their minds are more capable of handling dull subjects.
Here's my opinion for demonstrating the effects of acid. This should be done by an adult, an adult that knows what they are doing, or is at least capable of knowing how to handle when it goes bad. Take a tub of hydrochloric acid and put some steel in it and let the kids witness the power demonstrated by the acid on the wheel. Unfortunately I know for a fact, it's not a joking matter. I could have sent smoke signals with the reaction I had going on.
Go big or go home. Nobody cares how lemon juice changes the color of a penny, nor will the kid remember it 15 years later when he's dumping wheels into hydrochloric acid. Teach the