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.
Just a side note on the acid is bad for teeth. For those worried about the health of their teeth in this regard, drink a lot of colas, coffee and the like, I found a tooth paste available on Amazon called APAGUARD m-plus. It’s a Japanese tooth paste that includes nano hydroxyapatite, Ca10(PO4)6(OH)2. It works a bit like fluoride in helping to seal the small holes (tubes) and cracks in the enamel but also seem to help rebuild both the enamel and dentine of the teeth. It will also help with bones but if your gums are healthy probably doesn’t ever reach that level.
From what I have been able to find, this was developed by NASA to help rebuild the skeletal integrity of astronauts returning to earth. It’s also used as a coating for joining artificial joints with the natural bone.
I’ve been using it for about a year now and it seems to work well for me. The key factor for me was that other “sensitive” teeth tooth pastes my dentist has recommended seem to rely on including a mile pain killer as actually solving the problem. m-plus doesn’t list anything as a pain relief component (on Amazon but the labels are all in Japanese which I don’t read.)
Ah, the relevant pH is 7.4, not 5, so with negative ions slightly outnumbering positive. So I guess there’s another factor than numerical quantity in why they don’t bind the zinc. But “things staying in constant flux” sounds like it could be that factor, thanks :)
For the most part, and to my limited memory of chem...yes.
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.
Just a side note on the acid is bad for teeth. For those worried about the health of their teeth in this regard, drink a lot of colas, coffee and the like, I found a tooth paste available on Amazon called APAGUARD m-plus. It’s a Japanese tooth paste that includes nano hydroxyapatite, Ca10(PO4)6(OH)2. It works a bit like fluoride in helping to seal the small holes (tubes) and cracks in the enamel but also seem to help rebuild both the enamel and dentine of the teeth. It will also help with bones but if your gums are healthy probably doesn’t ever reach that level.
From what I have been able to find, this was developed by NASA to help rebuild the skeletal integrity of astronauts returning to earth. It’s also used as a coating for joining artificial joints with the natural bone.
I’ve been using it for about a year now and it seems to work well for me. The key factor for me was that other “sensitive” teeth tooth pastes my dentist has recommended seem to rely on including a mile pain killer as actually solving the problem. m-plus doesn’t list anything as a pain relief component (on Amazon but the labels are all in Japanese which I don’t read.)
I’ve been using the Boka brand of nano hydroxyapatite toothpaste.
It has a pain killer: methylsulfonylmethane.
I’m using it because it seems safer than flouride, but I don’t have much evidence, and I wasn’t trying to solve any specific problem with it.
Ah, the relevant pH is 7.4, not 5, so with negative ions slightly outnumbering positive. So I guess there’s another factor than numerical quantity in why they don’t bind the zinc. But “things staying in constant flux” sounds like it could be that factor, thanks :)