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I take it the concentration of H+ is inversely related to the concentration of negative ions, because if there's a high concentration of both, they'll just bind each other

For the most part, and to my limited memory of chem...yes.

H+ captures the acetate away from the zinc, but the negative ion doesn't then bind the Zn+

Umm. Hmm. *goes back and reads the relevant parts of your post* I don't know any of this off the top of my head. Let's see... Wiki says zinc acetate is a salt of zinc and acetic acid. Ok, so zinc acetate is already zinc ions and acetate ions. (CH3CO2-). Two of those ions for each Zn, so each Zn ion is Zn+2. You stick the Zn(CH3CO2)2 into the pH 5 saliva solution, which has a lot of extra H+ sticking around. The H+s in the pH 5 solution are already outnumbering any loose negative ions...that's what it means to be pH5. So when you stick the salt in it, the H+s grab the negative acetate ions and tear the salt structure apart. The Zn becomes free-floating ions because there aren't enough negative ions around to bind with them.

If you drop the zinc acetate in a neutral solution, it might still dissolve into ions; sometimes with water, what happens is basically everything just pulls at everything else, and things stay in constant flux instead of settling into neutral compounds. [This is my understanding of what happens with NaCl, for example: you don't get NaOH and HCl so much as you get lots of Na+ and Cl- floating around in H2O with the H+ and OH-, constantly forming and unforming all the possible combinations in insignificant amounts.]

I feel compelled to point out here that low pH values are bad for your teeth. Low pH destroys the protective biofilm and leaches phosphorus and the like out of the teeth, weakening them and leading to cavities. I only know this because I recently proofread a dentist's book all about it. So, like, maybe don't try to lower your saliva pH to get more zinc.


I have not the faintest clue about zinc or your overall question, but this part:

saliva pH is 5; over 100 times more acidic than pH of cellular environment which is 7.4
7.4 is basic, right? "100 times more acidic than [something on the other side of neutral]" seems like a weird thing to say?

pH is basically the (negative) exponent in the concentration of H+; a concentration of 10^-2 gives a pH of 2, a concentration of 10^-7 gives a pH of 7. So moving from 5 to 7 on the pH scale is a factor of 100 in the concentration of H+. That's why they say it's "100 times more acidic". (Also, the neutral point in the pH scale is neutral because that's the concentration at which the positive H+ ions are balanced by negative...usually OH-...ions.)

One problem I see with that analysis is this part:

After all, workers are producing 20% more, so the amount of profit from hiring an extra worker increases by 20%.

If demand isn't being met, or if it's elastic, then increasing your production = increasing your profits. But if demand for your product is not elastic, increasing your production will just leave you with unsold product and decrease your profits; you'd make more money by using those new machines to reduce your work force.

Answer by anna_macdonaldJun 30, 2019360

I have 7 kids, so I feel qualified to make some observations on this topic.

Kid #1 asked "why" questions all the time when she was young. As a teenager, her questions have definitely decreased in frequency. This is primarily because all the questions she had as a young child actually got answered. There was a LOT of low-hanging fruit, and she picked it when she was young. She is still curious; her teachers enjoy her genuine interest in learning. It competes with her love of fan fiction, though.

Kid #4 also has some curiosity, and asks questions, though not as often as Kid#1 ever did. He, too, has fewer questions as he ages.

Kids #2, 3, and 5 never actually went through a "why" phase. They ask "Why can't I have that candy bar?" but they don't ask "Why is the sky blue?" They ask practical questions about what, when, where, and they may be quite interested if there's an interesting demonstration of something, but curiosity isn't a big part of their makeup. I have also noticed other people's kids who aren't that curious. People who say that all young kids are curious are basing that on observations of kids who are. Confirmation bias: they aren't looking for kids who aren't curious.

Kid #6 isn't very curious, but she is extremely social and wants to always hear the sound of her voice and mine, so she asks lots of questions and then doesn't listen to the content of the answers. Kid #7 's vocab consists mostly of a handful of food items and "shoes", so her curiosity can't be gauged yet.

So I'd say it's not the case that most young kids are curious and lose that as they grow older. Rather, most young kids are not that curious, and continue not to be curious as adults. The kids who are uber-curious grow up to be adults who are still curious, but whose questions are less incessant because they find answers as they go.

I was making tea. I poured hot water into a travel mug. The interior sides of the travel mug were silver. The liquid looked yellow. (Before I put the tea bag in.) To see if the yellow contamination had come from the kettle that I had heated over the stove, I poured some of the remaining water into the sink. That water was clear, with no evidence of a yellowish tinge. The mug had been taken from a cupboard of clean dishes. I was fairly certain I had looked in the mug before using it and seen that it was clean. After seeing the yellowish liquid, I still saw no other indication that the mug might have been dirty (no gunk on the inside or outside). Just the mysteriously yellow liquid.

Guvf jnf n onq pnfr bs zbzzl oenva. V cbherq ubarl vagb gur obggbz bs gur zht svefg, gura sbetbg V unq qbar gung ol gur gvzr V cbherq gur jngre va. Gur ubg jngre vzzrqvngryl qvffbyirq gur ubarl, naq vg tnir gur jngre gur lryybjvfu gvatr. V fcrag svir zvahgrf gelvat gb engvbanyyl qvntabfr gur ceboyrz orsber erzrzorevat nobhg gur ubarl.

Conveying that is often worthwhile, but it's situational enough that simply stating the context of what you're doing is probably a better idea than formalizing a novelty scale.

Also, I didn't mention this above, but re-hashing stuff that isn't novel can be highly useful. Penetration of an idea into the population would never happen if people only ever pointed to the original source for an idea without conveying/spreading it themselves. It's helpful to have a million blog posts about the same thing, because each of those blogs is reaching a slightly different audience.

Answer by anna_macdonaldApr 20, 201960

The problem with a novelty scale is that novelty has a high degree of circumstantial/subjectivity to it. What's new to one person is old hat to another. Millions of people may independently recreate the same wisdom based on their life experiences, and that insight feels new to them, but might not be new to those they share it with. In the modern age, not even a google search can guarantee that an idea hasn't been laid out somewhere by someone.

Is the Letters site itself, the project you mention, or was one particular conversation on that page discussing the idea (if so, which one)?

Answer by anna_macdonaldFeb 20, 201980

Your definition of ruminating includes that you introspect on causes and consequences as opposed to solutions. The techniques you mention may include focusing on causes and consequences, but they are very solution-oriented.

If there is a difference in their successfulness, I think that solution-orientedness is why. People who ruminate are thinking about a problem without trying to solve it. That's, frankly, a depressing thing to do. Feeling like you have a problem that can't be solved is almost the definition of frustration, and just reminding yourself of a problem without any sense of moving forward or making progress will reinforce negative thought patterns without accomplishing anything.

By contrast, people who engage in focusing, IFS, and related techniques have a goal in mind. They're not just reviewing the problem and its causes; they're trying to get somewhere. There's an underlying optimism that is being fostered, especially if it works well enough for people to want to keep trying it.

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