100% Pure Silver

Discussion in 'Off-Topic' started by Lightfire, Jun 8, 2011.

  1. Lightfire

    Thread Starter Well-Known Member

    Oct 5, 2010
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    Hello folks,

    I am wondering if there is/are 100% pure silver/s that exist in our world. Is/Are there?
    I only heard of 99.9%, 99.99% pure silvers.

    So folks, do you think there is/are 100% pure silver/s?

    Thank you so much.

    Lightfire
     
  2. RiJoRI

    Well-Known Member

    Aug 15, 2007
    536
    26
    It can probably be done, if you wish to pay to remove the 3.1 mg of impurity from the 31.1034g in one Troy ounce!

    4 9's is probably "good enough for government work"!

    --Rich
     
  3. someonesdad

    Senior Member

    Jul 7, 2009
    1,585
    141
    One could answer either yes or no and be "correct". I could say yes by beaming a single silver atom through a vacuum and you'd have to call it 100% silver, at least until it collided with the walls of the chamber.

    However, we normally deal with groups of atoms in macroscopic quantities. In this context, there are two main aspects of your question: 1) how will you purify the silver? and 2) how will you measure it to verify it is of the purity you say it is? Both are quite hard, but the second one is probably the hardest.

    Let's suppose you found some very expensive supplier who gave you some silver that they claimed was 100% pure. As soon as you open its package in any environment we know how to create on Earth (and how would you verify it's not already contaminated?), it's going to be contaminated on its surface with non-silver atoms. This includes opening it as carefully as you could inside the best vacuum we're able to make. Thus, from a practical perspective, it's not possible to have 100% pure silver in macroscopic quantities. But some lab somewhere, if given enough resources, could make 100% pure samples for brief periods if there was enough motivation and resources. But virtually everyone would ask "why bother?".

    Ultimately, the real barrier to stating something is 100% pure is there's no way I can think of to non-destructively test the whole sample to verify there are no contaminant atoms. Perhaps the best method (off the top of my head) is x-ray fluorescence, but you're going to have to count x-rays with the sample in a superb vacuum for a long time -- and there will still be a finite probability you've missed a contaminant atom -- or get a false positive. Most other high-resolution tools are either destructive (e.g. neutron activation analysis), take just a small sample (e.g., atomic absorption spectroscopy) or will change the nature of the sample by e.g. ion bombardment.

    I've been away from this kind of work since the 80's, so someone's going to bring up something obvious that I've missed, so I'll just slap my forehead in advance... :p
     
  4. tom66

    Senior Member

    May 9, 2009
    2,613
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    I'm guessing 100% silver makes audio sound even better than 99.9999% oxygen-free copper. HDMI must look REALLY good. Those 1's and 0's look best when delivered through $120 of Monster cable, both in price and brand.

    In pure air, silver does not react with anything. So like most alkali metals are sent in oil, pure silver could be stored (very carefully) in a sealed atmosphere full of oxygen. In its purest form, silver has very high thermal conductivity, so you could try to measure its purity by heating it up, but it could be tricky and would likely introduce a lot of errors into your measurement.

    It's similar to 99.9% anti-bacterial sprays. Although such sprays may kill 100% of bacteria (which would be a bad thing), it's not possible to verify such a claim. A single bacterium could remain. The claim would then be false. 0.1% is quite a large amount, enough to make a germaphobe squirm.
     
  5. magnet18

    Senior Member

    Dec 22, 2010
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    We're constrained to a few nines because of random contaminants.
    Think about a ring, theres no way to guarantee that theres not a single copper atom in there somewhere or something.

    Good enough for anything we humans need at the present.
     
  6. Wendy

    Moderator

    Mar 24, 2008
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    Silver reacts quite nicely with oxygen, gold doesn't. Why does silverware tarnish otherwise?

    I've heard that silver tarnish (which I assume is silver oxide) conducts quite nicely.
     
  7. magnet18

    Senior Member

    Dec 22, 2010
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    IIRC, silver oxide semi-conducts nicely, silver itself conducts nicely.
    I might be confused.
     
  8. Lightfire

    Thread Starter Well-Known Member

    Oct 5, 2010
    690
    21
    So, in other words 100% pure silver is either not existing or difficult to get. Right?
     
    Last edited: Jun 9, 2011
  9. Wendy

    Moderator

    Mar 24, 2008
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    More or less. 100% of anything can be bogus.

    My job uses pure gold, industrial grade. It is 99.99% pure, by industry standards this is as good as it gets. If I were to steal this gold and try to cash it in the purity would flag the buyer, and if they were honest they would turn me in. Most gold used for jewelry is considerably less pure.
     
  10. Lightfire

    Thread Starter Well-Known Member

    Oct 5, 2010
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    How it came bogus?

    :D
     
  11. Wendy

    Moderator

    Mar 24, 2008
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    bogus = not real, fake, a lie.
     
  12. Lightfire

    Thread Starter Well-Known Member

    Oct 5, 2010
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    Yes, I looked up in dictionary.:DSo, now, how it comes fake?;):D
     
  13. Wendy

    Moderator

    Mar 24, 2008
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    If someone claims 100% then look very closely at what they are saying. 100% silver or gold is an approximation, but you'd have trouble telling the difference between 99.99% and 100%.

    Another thing (off subject a bit)... If someone tells you they are telling the truth then they may not be, why would they have to declare it is so otherwise. Ditto with someone claiming "I'm an honest man!". If they are really honest then they don't have the need to declare it is so.
     
  14. Lightfire

    Thread Starter Well-Known Member

    Oct 5, 2010
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    Ahh, like what I have thought.:D
     
  15. magnet18

    Senior Member

    Dec 22, 2010
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    Now think about this. Suppose someone tells you they are lying...
     
  16. Wendy

    Moderator

    Mar 24, 2008
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    Then they are honest.
     
  17. atferrari

    AAC Fanatic!

    Jan 6, 2004
    2,648
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    Bill, the one you use for soldering at work, it comes in fine wires, small pieces or what?

    Can you describe briefly what is the handling you give? Curious about that.

    What are the dimensions involved?

    Gracias.
     
  18. Wendy

    Moderator

    Mar 24, 2008
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    No soldering. Gold and aluminum wire (we use gold) come in 0.0007", 0.001, and occasionally larger. Ours is 1 mil wire. A typical IC pad is 3.5 to 5 mils square. The gold wire is off of spools around 300'.

    The industrial process is thermocompression bonding, ball bonding. It is the method wires are attached to chip die. There are variations, such as wedge and ribbon bonding, but all of them use carefully calibrated ultrasonic, heat, and pressure to merge wires into pads. It works very well, and is pretty much the preferred technique for chips. Other variations are flip chip bonding, where gold balls are bonded onto the IC, wires are removed, and it is flipped over and bonded to a ceramic substrate, pretty similar to ball grid array.

    Gold is an odd material. Press two pieces of gold together, and they will slowly merge. The ultrasonics, heat, and pressure speed up this process. Aluminum does this too, but not nearly so well.

    http://en.wikipedia.org/wiki/Wire_bonding
     
  19. magnet18

    Senior Member

    Dec 22, 2010
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    But since they are honest and they told you they are lying then they are actually lying, which means they are honest, which means they are lying...

    Also, about the gold, would passing a current through 2 pieces speed up the bonding process?
     
  20. Wendy

    Moderator

    Mar 24, 2008
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    A little, but the nature of the material will do it better. Gold grows dendrites, which is terrible in solder, but great for this process.

    The older process was thermocompression, the new thermosonic. I misspoke myself earlier.

    The old process used a lot more heat (190°C typical) and a capillary (hollow tool, similar to sewing), and a hydrogen flame to make the ball.

    The new process uses a lot less heat (125°-150°), ultrasonics, capillary, and a electric arc to make the ball.
     
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