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Re the educational aspect -- when I ask students in my university class whether they remember Avogadro's number from high school, they all respond in the affirm

Re the educational aspect -- when I ask students in my university class whether they remember Avogadro's number from high school, they all respond in the affirmative. When I ask them for the mantissa, the whole class sings out "6.02". Great! But, when I ask for the exponent, they are really quite uncertain. For many, the rote learning has cut off after the "times ten to the" in the sentence. This is disappointing, but at least it provides me an opportunity to talk about what digits actually mean. If I were a psychologist (shudder) interested in how learning works, I'd be inclined to see whether the students who get exponents wrong are the same as those who have no idea how to handle significant units. My guess is that they are. I think the problem is that the core ideas of decimal notation are lost on many learners, because all digits are equal on a calculator, so getting the "2" wrong in Avogadro's number seems to be the same as getting the "6" wrong. If I had a magic wand to wave, I'd use it to bring back slide rules. (Oh, and I'd bring back low grades for weak work, but that also would not fly with school boards.)

thrower123 8y ago
I remember that there is such a thing, and the relation between the number of molecules and a gram. But the exact number? No way - that's just not useful information to keep in my head post junior year chemistry. I've never had cause to need that information, especially when it is a google away.
- JoeAltmaier 8y ago
  That's kind of a self-fulling prophesy or something. Not having knowledge about something means, we work around it, fake it or just ignore it. For instance you might have wondered how much weight you lose with each breath. Converting O2 to CO2 means you're losing some mass of carbon each exhalation and that's a major channel for weight loss. But not remembering much about chemistry, nothing comes of this. Another part of our lives remains shut off because its easier to ignore it. Not terribly important I guess. But add up the thousands of times we move ahead without real information or curiosity, and our lives are diminished. No, I'm not ready to be proud of how I lost most of my technical knowledge about the world, and how I blunder on in ignorance because its easier.
  - SamBam 8y ago
    > means you're losing some mass of carbon each exhalation and that's a major channel for weight loss. Indeed, that's almost 100% of weight loss, except for some daily fluctuations like water weight and what happens to be inside your gut at the moment, right? That's virtually the only way that body actually loses its own mass.
    - JoeAltmaier 8y ago
      Chemistry gives your kidneys things to eliminate along with urine too?
pbhjpbhj 8y ago
6E23! It rhymes. If they can remember "6E" and that it rhymes, then the first number after 3 they come to that rhymes is 23. Atoms in 1g Of 12C? It's 6E 23.
- SamBam 8y ago
  ...in 12g, surely?

thrower123 8y ago

I remember that there is such a thing, and the relation between the number of molecules and a gram. But the exact number? No way - that's just not useful information to keep in my head post junior year chemistry. I've never had cause to need that information, especially when it is a google away.

JoeAltmaier 8y ago
That's kind of a self-fulling prophesy or something. Not having knowledge about something means, we work around it, fake it or just ignore it. For instance you might have wondered how much weight you lose with each breath. Converting O2 to CO2 means you're losing some mass of carbon each exhalation and that's a major channel for weight loss. But not remembering much about chemistry, nothing comes of this. Another part of our lives remains shut off because its easier to ignore it. Not terribly important I guess. But add up the thousands of times we move ahead without real information or curiosity, and our lives are diminished. No, I'm not ready to be proud of how I lost most of my technical knowledge about the world, and how I blunder on in ignorance because its easier.
- SamBam 8y ago
  > means you're losing some mass of carbon each exhalation and that's a major channel for weight loss. Indeed, that's almost 100% of weight loss, except for some daily fluctuations like water weight and what happens to be inside your gut at the moment, right? That's virtually the only way that body actually loses its own mass.
  - JoeAltmaier 8y ago
    Chemistry gives your kidneys things to eliminate along with urine too?

pbhjpbhj 8y ago

6E23! It rhymes. If they can remember "6E" and that it rhymes, then the first number after 3 they come to that rhymes is 23. Atoms in 1g Of 12C? It's 6E 23.

SamBam 8y ago
...in 12g, surely?