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Periodically Speaking
Sep. 23rd, 2022 02:06 pmK is now taking high school chemistry and mentioned last night that their instructor expects them to memorize the periodic table. Personally, I think that this is a rather silly expectation, because there are large stretches of the periodic table which normally don't need to be considered, other than being cognizant that there are elements sitting there that you may run into (or not) that have interesting properties and/or you only need to know about as a group. For example, you're unlikely to encounter any of the actinides past americium (see your smoke detector), nor any of the elements that follow the actinides (where we haven't managed to make any that don't decay in seconds or less). And the lanthanides are mostly interesting as a group which have a lot of special purpose usages, but which are otherwise ignorable (assuming that China doesn't cut off our imports).
On the other hand, there *are* things about the periodic table that are worth knowing. And so I explained to K about the s shell and the p shell and how those electron shells are what's important in the first few rows of the periodic table. And how it's worth learning the first ten elements in order (hydrogen, helium, lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, neon), because those set the most important columns in the periodic table. And how it's worth knowing the noble gases, the halogens, the alkali metals going down the columns. And how the elements in the third row of the periodic table are like the elements in the second row of the periodic table. And you need to know iron, and therefore also cobalt and nickel that follow it, while the elements below that are the platinum group, which are interesting. And from there, you duck right and find copper, silver, and gold stacked atop one another. And lead and bismuth, the heaviest stable (or very nearly stable) elements.
By the time I had gotten done scribbling on a sheet of scratch paper, I had filled in *huge* tracts of the periodic table. But not nearly a case of memorizing the whole thing.
Because memorizing the whole thing is a silly exercise. :)
The good news was that K remained entertained by the whole show.
On the other hand, there *are* things about the periodic table that are worth knowing. And so I explained to K about the s shell and the p shell and how those electron shells are what's important in the first few rows of the periodic table. And how it's worth learning the first ten elements in order (hydrogen, helium, lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, neon), because those set the most important columns in the periodic table. And how it's worth knowing the noble gases, the halogens, the alkali metals going down the columns. And how the elements in the third row of the periodic table are like the elements in the second row of the periodic table. And you need to know iron, and therefore also cobalt and nickel that follow it, while the elements below that are the platinum group, which are interesting. And from there, you duck right and find copper, silver, and gold stacked atop one another. And lead and bismuth, the heaviest stable (or very nearly stable) elements.
By the time I had gotten done scribbling on a sheet of scratch paper, I had filled in *huge* tracts of the periodic table. But not nearly a case of memorizing the whole thing.
Because memorizing the whole thing is a silly exercise. :)
The good news was that K remained entertained by the whole show.