Tin: Difference between revisions
Jump to navigation
Jump to search
(Created page with "{{Compound|name=Tin|chemf=Sn|density=7.365|mp=231.93|bp=2602|num=50|group=Metalloids|stp_p=solid|stp_q=grey|mm=118.7|nfpa_h=1|nfpa_f=0|cote=23.8|nfpa_r=0}} ==Uses== ===Primary...") |
JeffEvarts (talk | contribs) |
||
| (4 intermediate revisions by 2 users not shown) | |||
| Line 2: | Line 2: | ||
==Uses== | ==Uses== | ||
===Primary=== | ===Primary=== | ||
* as a component of | * as a component of bronze, brass and pewter. | ||
* as a component of '''solder''' | * as a component of '''solder''' | ||
===Secondary=== | ===Secondary=== | ||
* tin is a useful structural material where its malleable nature is used, such as hinges or crimpable fasteners | * tin is a useful structural material where its malleable nature is used, such as hinges or crimpable fasteners | ||
| Line 17: | Line 18: | ||
** β- or "white" tin which is silvery, ductile and metallic. | ** β- or "white" tin which is silvery, ductile and metallic. | ||
* At 13.2 °C and below, pure Β tin transforms to α-tin | * At 13.2 °C and below, pure Β tin transforms to α-tin | ||
* At 100°C and above α-tin reverts to Β-tin. | |||
==Production== | ==Production== | ||
===Extraction=== | |||
* Carbothermic reduction of [[cassiterite]] | * Carbothermic reduction of [[cassiterite]] | ||
== | Reduction of tin with carbon is not an easy process since the free energies of reduction are unfavorable. | ||
: {{#Chem:SnO2 + C = Sn + CO2 dH=+125.2 kJ}} | |||
However, reduction with carbon monoxide is considerably less unfavorable. For the reaction | |||
:{{#Chem: SnO2 + CO = SnO + CO2 dH=+5.5 kJ // First oxygen }} | |||
:{{#Chem: SnO + CO = Sn + CO2 dH= -0.3 kJ // Second oxygen}} | |||
:{{#Chem: SnO2 + 2CO = 2CO2 + Sn dH=+5.2kJ //'''Net'''}} | |||
==Testing== | ==Testing== | ||
==Storage== | ==Storage== | ||
| Line 25: | Line 35: | ||
==Disposal== | ==Disposal== | ||
==See Also== | ==See Also== | ||
* [http://www.geevor.com/media/Smelting.pdf Smelting Tin] at Geevor Museum | * [http://www.geevor.com/media/Smelting.pdf Smelting Tin] at Geevor Museum | ||
* [http://www.pdmhs.com/PDFs/ScannedBulletinArticles/Bulletin%2013-2%20-%20An%20Analysis%20of%20the%20Processes%20for%20Smelting%20Tin.pdf An Analysis of the Process of Smelting Tin], The Bulletin of Peak District Mines Historical Society Vol 13 No 2 Winter 1996 | * [http://www.pdmhs.com/PDFs/ScannedBulletinArticles/Bulletin%2013-2%20-%20An%20Analysis%20of%20the%20Processes%20for%20Smelting%20Tin.pdf An Analysis of the Process of Smelting Tin], The Bulletin of Peak District Mines Historical Society Vol 13 No 2 Winter 1996 | ||
==References== | ==References== | ||
<references/> | <references/> | ||
Latest revision as of 07:02, 17 November 2019
| Chemical formula | Sn |
|---|---|
| Atomic Number | 50 |
| OTP appearance | grey solid |
| Molar Mass(g/mol) | 118.7 |
| Density(g/cc) | 7.365 |
| Melting Point(°C) | 231.93 |
| Boiling Point(°C) | 2602 |
| Coefficient of Thermal Expansion(×10-6 °C-1) | 23.8 |
| NFPA 704 |  0
1
0
|
Uses
Primary
- as a component of bronze, brass and pewter.
- as a component of solder
Secondary
- tin is a useful structural material where its malleable nature is used, such as hinges or crimpable fasteners
Natural Sources
- Elemental tin does not occur naturally
- -oxide occurrs naturally as cassiterite
Hazards
- Virtually all organotin compounds are highly toxic
- At temperatures below 14°C, tin undergoes an allotropic change which changes the tin from a metallic form to a nonmetallic form. This is called "tin blight" or "tin pest". This process slowly reverses above 14°C and is rapidly reversed above 100°C.
Character
- Tin has two important allotropes:
- α- or "grey" tin which is grey, brittle, and nonmetallic.
- β- or "white" tin which is silvery, ductile and metallic.
- At 13.2 °C and below, pure Β tin transforms to α-tin
- At 100°C and above α-tin reverts to Β-tin.
Production
Extraction
- Carbothermic reduction of cassiterite
Reduction of tin with carbon is not an easy process since the free energies of reduction are unfavorable.
- SnO2 + C → Sn + CO2ΔH=+125.2 kJ
However, reduction with carbon monoxide is considerably less unfavorable. For the reaction
- SnO2 + CO → SnO + CO2ΔH=+5.5 kJ // First oxygen
- SnO + CO → Sn + CO2ΔH=-0.3 kJ // Second oxygen
- SnO2 + 2 CO → 2 CO2 + SnΔH=+5.2kJ // Net
Testing
Storage
- stacked as ingots, keeping the temperature above 14°C
Disposal
See Also
- Smelting Tin at Geevor Museum
- An Analysis of the Process of Smelting Tin, The Bulletin of Peak District Mines Historical Society Vol 13 No 2 Winter 1996