I rarely entered science fairs as a student, but when I was in the seventh grade, everyone in the class was required to submit some project to the school science fair as part of our Science grade. I moaned at home about needing a topic, and my father suggested I do something on how metals reacted when exposed to various liquids.
Huh? I had no idea what he was talking about.
“Do you know what rust is?” he asked. When I nodded, he explained how rust was formed, how metal oxidized when it was exposed to different chemicals, and how different metals reacted differently to different substances.
It still seemed like Greek to me.
My father worked in the metallurgy group at the Hanford Engineering Works near Richland, Washington. He had access to samples of various metals. He brought some of the samples home, and we (he) devised the experiment. We would weigh the metal samples, dip them in liquids such as water and milk, then see whether their weights had changed. That would show whether the metal had oxidized.
As I recall, we had five different metals and dipped them into five different liquids, for a total of twenty-five variants. I know we had samples of iron, magnesium, and copper. I think aluminum was another, but I don’t recall the fifth metal. As for the liquids, we had tap water, distilled water, hydrochloric acid, milk, and something else—maybe orange juice.
Dad weighed the samples on a scale at work that could measure down to the hundredth of a milligram. Then, on the picnic table on our back porch, we carefully measured the same amount of liquid into each container. I think the containers were baby food jars—my brother was an infant that year, and we had lots of baby food jars in the house.
When the liquids were ready, we tied a wire around each sample and lowered it into a jar. It was a pretty boring experiment until we dropped the magnesium into the hydrochloric acid.
WHOOSH! The acid immediately ate through the wire, dropping the magnesium to the bottom of the jar, where it fizzed and roiled until acid bubbled out onto the picnic table. Dad grabbed the baby food jar and threw it into the yard. There would be a brown streak in the grass all that season where the acid burned it away. The stain on the picnic table lasted even longer.
“So what does that teach you, Theresa?” Dad asked, though I think he was as surprised as I was by the result.
“Magnesium reacts strongly to hydrochloric acid.”
That was the upshot of our experiment. We left the other metal pieces in their baby food jars for twenty-four hours before taking them out to be weighed again. Most of them showed very little change in weight. But the magnesium, even after its brief bath, had been eaten away appreciably.
After the second weighing, Dad showed me how to write up the chemical equations to describe what had happened. Frankly, I don’t remember how that formula worked. The only chemical formula I remember now is
Acid + Base = Salt + Water
Our formula may have been something like
Metal + Acid = Salt + Hydrogen
Once Dad was sure I understood the science behind our experiment, I wrote my report, titling it “The Chemical Reactivity of Metals.” Then I designed the display backboard, complete with tables of results and graphs from the report, and set it up in the school gym for the science fair.
I won a prize in our school’s fair, which qualified me to go on to a city-wide science fair. There I won a $25 savings bond, which my father put in his safe deposit box. Many years later, I cashed it in.
This was one of the few times my dad helped me with a school assignment. I didn’t usually need help. But on this occasion, I relished the chance to discover just little bit of the kind of things he worked on in his job.
Though my project, “The Chemical Reactivity of Metals,” was a far cry from his published reports, one of which was titled, “Fabrication History of Alloys Used in the Irradiation Effects on Reactor Structural Materials Program.” Huh?
And when I got to Chemistry in high school, I was ready for those pesky formulas we had to learn. Maybe that’s why I liked Chemistry better than my other science courses.
When do you remember your parents helping you with school work?
