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Letter 0740
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Todd Huehn |
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--- Here is some info, try looking around the World Wide Web under tin whisker. I found these from AMP Corp.: Good luck.
You might be better off hunting the website of engineering universities like Stevens in Hoboken. We have to deal with tin pest in the finishing business, but I don't know the mechanism. The above article says it is caused by stress in the deposit from electroplating, suggesting to a non-scientist like me that the crystals are deformed and have missing or have extra ions in the lattice causing pressure, and relieve the stress by changing shape and moving into these whiskers. You might want to look into the crystal structure of tin as the original letter suggests. Look into adding bismuth or lead into the plating bath as a cure. Tom Pullizzi Ed. note: Unfortunately those URLs no
longer work (2008) so we struck them thru.
I am presently working on a CD-ROM
project on the physics of matter and I am looking for a
photo/image/video which can illustrate the "tin pest". Up to
now, the best I could find by browsing the web are plain
texts describing the phenomenon and a nice photo of tin
whiskers at Alain FILHOL
The only photos I've seen (black and white, no less) go all the way back to "Alkaline Tin and Tin-Bismuth Plating with Insoluble Anodes" by J.C. Jongkind, published in Plating, Vol 55, No. 7, July 1968.
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I was looking for 'tin pest' on the web because I have a very old tin teapot (I guess about 150 plus years old) and it lost its shiny tin cover. Lately it was sort of vibrating and my wife mentioned it to my father, who has graduated from a Dutch Nautical Institute before WW2. He was the one who mentioned the words 'tin pest' to me and this is why I looked it up. Please note that this teapot has never been in temperatures below 10 degrees Celsius and still it was subject to flaking, etc. It is just very old. Maybe this knowledge is of help.
Siets Meijer
- Maturin, Monagas, Venezuela
It was vibrating!? I think your teapot has a special variety of
tin pest closely related to the larva worms in jumping beans, Siets
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 Ted Mooney finishing.com Brick, New Jersey |
So sorry, just vibrating, no larvae or jumping beans =). Siets Meijer
Siets Meijer
- Maturin, Monagas, Venezuela
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I am doing a lab report for my chemistry class. The extension question is as follows:
Sometimes extreme physical changes result in permanent changes in the nature of a substance. Investigate the phenomenon of tin pest. What causes this physical change?
Could anyone help me out? I am desperate!
Jen B
student
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- I am doing extra credit for my chemistry class and my assignment was to investigate "tin pest". To find out what it is or whatever. If anyone can give me a website or if someone can tell me I would be very appreciative. Thanks so much, Lacey
L
Hello, I'm doing the same lab as Jen, and I could find little information on tin pest. The question is as follows: "Sometimes extreme physical changes result in permanent changes in the nature of a substance. Investigate the phenomenon of tin pest. What causes this physical change?" If anyone at all would please point me towards the correct direction as to where I could find information on this online - or what it is for that matter .... Thank you in advance. Aeone
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Napoleon, during his advance on Moscow during the severe Russian winter experienced this "disease", (or rather his poor squaddies). The soldiers' buttons, made of tin, crumbled to dust. This is because Tin goes through a change in crystal form at low temperatures to a less crystalline (more amorphous) form.
ROSS MACDONALD
Tin is stable in the beta form (allotrope) at room temperatures but will change to the alpha form at low temperatures (actually below 13.2 deg C, though much lower temperatures are needed for observable transition, the lower the temperature the faster the transition). The alpha form has a much weaker structure, hence the buttons of Napoleon's troops turning to dust in the harsh Moscow winter. When the temperature rises the situation becomes worse (for buttons) because the transition back to the beta form introduces crystalline faults. "Chemistry of the Elements" [link is to book info at Amazon], Greenwood and Earnshaw, will explain further.
Angie Jamison
- U.K.
I am a student at Chamblee High School in Georgia. I have a Chemistry question for you. I was wondering if you could help me with it. The question is Sometimes extreme physical changes result in permanent changes in the nature of a substance. Investigate the phenomenon of tin pest. What cause this physical change? Would you please help me in I really could use it Thanx P.S. If possible can email me back tomorrow or ASAP. Thank You.
Aisha
student - Lithonia, Georgia
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. Uh . . . Aisha . . . now I understand why some teachers ask us to respond to all student questions with: "Do your own homework!" :-) You googled and found this page, and didn't even read the one page, but instead you ask someone to do your homework and e-mail it to you. C'mon now, you can do better :-)
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i am also a student at Chamblee high and from the information i have gathered i think tin pest is that when pure tin is exposed to temperatures below 10 degrees Celsius it deteriorates or flakes off into a powder.
n. y.
- Stone Mountain, Georgia
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. I just wanted to thank you for providing me with info. on the tin pest. I, like the other 20 high school students who sent in a question, had the same exact chemistry lab question regarding tin pest, and unlike them, I took the time to read through this web site and gather my answer that way. It was a great help, and thank you again. Emily
D
This has been a helpful site to me and many other friends of mine who were struggling to do that same darn chemistry lab question. All we had to really do is investigate the phenomenon. We just combined the info around this site, to get a good, almost-precise answer. Ben C
Thanks for taking the time to write, Emily and Ben! It is great to hear that people's efforts weren't wasted :-)
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Hi, guess what, I had the exact same chemistry question. (I guess chemistry teachers are big on sharing.) Anyway this site helped a lot. Thankee kindly.
Elenor D
- Pasadena, California
awww, shucks, ma'am, we're just turning red faster than a tin can goes from beta to alpha in North Dakota come January.
- The editors of finishing.com
wow!, this question about tin pest on chemistry labs seems to be a pretty popular question.. I myself had the same exact question to answer. I was able to gather just about all the info i needed from this site. Well, I would just like to say thanks to all those experts out there willing to share their time to help out us students. Thanks guys!
Mike A
- King of Prussia, Pennsylvania
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. This Site was a great help with my research on Tin Pest. I like the plethora of others had this question on my lab sheet. So thanks for the help. This site was a great source. Mike W |
El Guapo: "And, Jefe, what is a 'plethora'?" |
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I just think it's funny how we all have the same question. I sure hope you all are right, though. If all the teachers can conspire against us to give us this lab, we can conspire with them and share answers! B.T.W., wasn't that a fun lab!!! Anyone have any accidents with the silver nitrate?
Matthew H
student - Cedar Bluffs, Nebraska
I, just like every other student who took time to read this page, not only had fun reading the redundancy of fellow students, but learning the answer to a much-asked question. Thank you for your information, and good luck to other high school chemists!
Thanks again, Meg
P.S. Does anybody else think they should update the questions is text books?!?
Meg E
student - Rhode Island
Ed. note: nah.....
I think it's cool how everyone has the same lab book! This page was really helpful.
Now i know why Napoleon never reached Moscow. His troops couldn't fight AND hold up their buttonless britches!
Science and History class come together!
Tiff G
student - St. Mary Academy, BayView, Rhode Island
Tin pest, as many people have said above, is caused by a change of state in the tin. The tin we all know and love is normally bright silver and crystalline. If you get a piece of pure tin and bend it, it will give out a noise. This is called "tin crying" and is caused by the tin crystals distorting against each other.
However, if tin is exposed to low temperatures the silver grey metal changes from the beta state (or crystal form) to the alpha state (or crystal form). This theoretically occurs at about 18 C, but the impurities in the tin force this temperature down - the more impurities, the lower the temperature. It is very difficult to get pure tin, most commercial tin is about 99.5% pure and this is enough to drop the transition temperature to quite low levels. Alpha tin is a manky grey powder. There is a story, which I cannot confirm, that at the end of the C19th a Russian Czar had a shipment of tin sent across Russia and when it arrived it was the horrible grey type. The Czar's officials thought the man who transported it had robbed the Czar and he was put to death. It is also claimed that Napoleon's troops suffered from tin pest when the buttons on their tunics fell to pieces because of the very low temperatures. I cannot confirm this because I wasn't around then!
I hope this is of interest and helps anyone who is eager to improve their continued education.
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Trevor Crichton |
Tin pest has been well know in the north of Sweden as the Sami peoples spin thread from it to decorate their clothes with. The tin of today can take -40 degrees or more (that the same on both F. and C. scales) The tin is first purified and then a couple of percent of pure silver is added. This information comes from a book called "TENNTRADSBRODERIER" by Mona Callenberg. She claims that tin has a tetra cristalen above 13 degrees C. and s cubical cristalen form.
Tim Honn
- Stromsund, Sweden
Monmouth Academy's Junior Chemistry Class was lucky enough to have that same text book that is so often mentioned throughout this website. I too scanned the internet in search of information on Tin Pest, and was thrilled to find a single site that completely answered my question! I appreciate everything you've provided and hope that you understand how much you've helped high school students around the world!!
THANK YOU!
Rebecca E
student - N. Monmouth, Maine
I have a son in high school taking Junior chemistry too, Rebecca. Won't it be funny if he gets the same question and searches the billions of pages of the world wide web, only to find his father's site :-)
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I have found some interesting and similar stuff about solders and soldering in "how to do" type literature published by Johnson Mathey Metals (dating from the 1950's). It seems that a little silver will improve things greatly. The consequences of what might happen to a space satellite going into earth shadow when cheap solder has been used hardly bear thinking about!
David Benyon
- Bude, Cornwall, England
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Hello all!
I am a high school student doing research of my own on Tin. I just thought I would add that other sources have stated that tin changes colour at about 13.2 degrees Celsius. Also, here is another interesting fact - in Medieval Europe, when tin organ pipes turned colour because of temperature change, it was thought to be the "devil's work." Keep up the great work and thanks for a great website!
Sarah F
student - Listowel, Ontario, Canada
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++++ As an interesting sidelight, there is a book just published called "Napoleon's Buttons". The title refers to the theory that the buttons on Napoleon's soldier's uniforms were made of tin, and in the cold Russian winter, they crumbled into powder. The result was that the soldiers were so cold, and spent so much effort trying to keep warm, they lost the war. Robert Wilson |
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I have a copy of "Tin: Its Mining, Production, Technology & Applications" [link is to info about the book at Amazon], copyright 1949 by C. L. Mantell
The author devoted several paragraphs to tin pest. White tin (tetragonal) is stable down to 18°C. Below that, the stable phase is gray tin (cubic). The transformation is very slow, so tin objects do not spontaneously crumble into gray powder. The transformation begins to accelerate rapidly at -20°C, peaking at -45°C. The implications are large for electronic devices used in cold climates. Old solders were tin-lead, while recent solders are either tin-antimony or tin-silver.
Joseph Greene
heat treating furnaces - Cherry Valley, Illinois
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++++ To add on to an earlier comment, the book Napoleon's Buttons goes on to say that the story is difficult to confirm for two reasons. First, people in Napoleon's time were well aware of tin disease, and Napoleon probably would not have permitted pure tin buttons on his army's uniforms. Second, tin does not disintegrate rapidly when exposed to cold--it's a slow process, even at the freezing cold temperatures in Russian in 1812. Noel Lee Ed. note: True or not, it is a very cute story and it inspires interest in students, so let's keep the story alive. No Mythbusters allowed on this one :-)
++++ Hey y'all I just wanted to say that I am so greatly amazed by the majority of questions based on the same lab that we have all encountered. It's reaaaaaallly funny, though, that the question is verbatim. Thanx FINISHING.COM! All your answers really helped! ~*~zee~*~ Zeinab Z
++++ Hey guys, I am doing the same exact lab right now. with the same exact extension.... the following website was where I found why the tin disintegrates http://palimpsest.stanford.edu/byform/mailing-lists/cdl/1998/1218.html Hope it helps Meg M
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Very interesting discussion. I have been involved in the soldering industry for 30 years and have some experience of the problem in the electronics arena. Certainly NASA did report this problem back in the sixties which lead to antimony being made a requirement in the then federal QQS solder specifications even though the alloy used was not pure tin but 60/40 Sn/Pb. Adding between 0.2 and 0.5%Sb made the alloys much less prone tin pest. I am sure it didn't prevent it totally but delayed the onset to a lower temperature. With the global transition to lead free solders the likelihood of tin pest occurring could increase. Space applications will continue to use lead containing solders for the foreseeable future though.
Chris Ward
- London, U.K.
As mentioned in an earlier posting, there has been published a
fairly popular book called
"Napoleon's Buttons: How 17 Molecules Changed History" [link is to info about book on Amazon], by P.
Couteur and J. Burreson of British Columbia. In this book they make,
or remake the claim, that one of the reasons for the defeat of
Napoleon's Grande Armeé in Russia was that his solders had tin
buttons. The argument is that in the cold of the Russian winter the
normal, white tin turned to gray tin (tin pest), which has no
structural integrity and as a result the solders could not keep their
coats closed and this facilitated their freezing to death.
This scenario is highly unlikely for at least a couple of reasons.
First, most of Napoleon's armies (not his Egyptian expedition at
least) had previously spent considerable amounts of time in
temperatures below 13.2 C, the transition temperature of tin. Even if
one makes the argument that tin pest is more likely to occur at
around -30 C, certainly several of Napoleon's armies spent
considerable time slogging through the Alps and other mountains of
Europe for weeks or months on end. No mention of this supposed
problem has come to light from these forays into cold climates.
Virginia Shaw Medlen in her history of the Irish volunteer unit of
Napoleon's forces "Legion Irlandaise (Napoleon's Irish Legion) 1803 –
1815" states: "Buttons were gold for officers and brass for other
ranks." Some brasses contain tin (1% tin is common for certain
types), but they were certainly did not contain 100% tin or even the
tin concentration levels of modern lead-free (SnAgCu) alloys, all of
which contain at least 85% tin.
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Also, the following quote [P. Britten-Austin, "Napoleon's
Lost Army: The Soldiers Who Fell", BBC History Webpage] has
been found: "Now, 183 years later, the splendid museum in
Vilnius displays many objects relating to the Napoleonic
adventure. What's this button, made of an alloy of COPPER
AND TIN (CAPITALS added by me), stamped '61? It comes from a
blue uniform jacket, almost certainly that of a Dutchman.
For the 61st Line Regiment was made up largely of (mostly
unwilling) conscripts from the Netherlands."[sic] Beverley
Christian
+++++ Hi guys, thanks for the very helpful website. I, a student, took the time to read through this and have finally answered the elusive "Sometimes physical changes result in permanent changes in the nature of a substance..." question. However, I'm a little confused on what an allotrope is. On other sites, allotropes are defined confusingly or are not mentioned at all. Is an allotrope just the beta state of tin? Elizabeth S
+++++ Thanks for the kind words, Elizabeth. A student should keep a dictionary at the ready, because you lose continuity and focus jumping all over the web. If you look this word up you will find that an allotrope is: "each of two or more different physical forms in which an element can exist. Graphite, charcoal, and diamond are all allotropes of carbon." Hopefully this 'permanent changes in the nature of a substance', and Napoleon's buttons turning to dust in the cold, and allotropes, all come together and make sense?
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