20
10/10/12 Lliçó 0 34 Sir William Ramsay

Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

  • Upload
    buidang

  • View
    215

  • Download
    0

Embed Size (px)

Citation preview

Page 1: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 34

Sir William Ramsay

Page 2: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 35

Tejas Kansas

Page 3: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 36

Neon

Page 4: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 37

Page 5: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 38

Elements

•  Preparació del Bromur de Alumini

Page 6: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 40

El Carboni (C )

Page 7: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 41

Page 8: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 42

Page 9: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 43

Diamant

Page 10: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 44

Page 11: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 45

Formes Alotròpiques del C

Page 12: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 47

Page 13: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 48

Tungstè Fausto i Juan José Elhuyar

Page 14: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 49

Tungstè[Swed.,=heavy stone], metallic chemical element; symbol W; at. no.74; at. wt. 183.85; m.p. about 3,410°C; b.p. 5,660°C; sp. gr. 19.3 at20°C; valence +2, +3, +4, +5, or +6. Tungsten is a very hard, silver-white to steel-gray metal with a b ody-centered cubic crystallinestructure. In its chemical properties it resembles molybdenum, theelement above it in group VIb of the periodic table. It is sometimescalled wolfram, and the chemical symbol is taken from this name; innaming compounds of tungsten, use of the name wolfram as a root ispreferred. Tungsten is one of the most dense metals and has ahigher melting point than any other metal. Pure tungsten is d uctile,and wires made of it, even those of very small diameter, have a veryhigh tensile strength. The element is resistant to ordinary acids andaqua regia but dissolves in a mixture of hydrofluoric and nitric acids.It forms compounds with carbon, chlorine, oxygen, sulfur, and someother elements. It is hexavalent in its most important compounds. Itforms tungstic acid (H2WO4), or wolframic acid, which is the basis ofa series of salts called tungstates, or wolframates. Tungsten metal isused extensively for filaments for light bulbs and electronic tubes.Carboloy, stellite, and tungsten steels are of importance in industrybecause they retain their hardness and strength at hightemperatures. Tungsten is usually added to steel in the form offerrotungsten, obtained by the reduction of ferrous tungstate in anelectric furnace. Tungsten carbide is u sed in place of diamond fordies and a s an abrasive. Sodium wolframate is used in thefireproofing of fabrics, in the weighting of silk, and as a mordant indyeing. Tungsten does not occur uncombined in nature; largedeposits of its ores are found in various parts of the world. Thetrioxide occurs in nature as the mineral wolfram ochre; scheelite andwolframite are the chief wolframate minerals. Tungsten is usuallyprepared from the trioxide by reduction with hydrogen or carbon.Tungsten was first isolated from tungstic acid in 1783 by the deElhuyar brothers.

Page 15: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 50

Lance ARMSTRONG

Page 16: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 51

Page 17: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 53

Vanadis. Andrés Manuel del Rio

Page 18: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 54

Descubrimiento VanadioEn 1801, al examinar muestras minerales procedentes de Zimapánen el actual Estado de Hidalgo en México, Andrés Manuel Del Ríollegó a la conclusión de que había encontrado un nuevo elementometálico. Preparó varios compuestos con él y al observar ladiversidad de colores que presentaban, lo denominó "pancromio"(muchos colores, en griego). Poco después, al observar que loscompuestos calentados cambiaban su color al rojo, denominó alnuevo elemento como eritronio (eritros, significa rojo en griego).Un año después entregó muestras que contenían el nuevo elemento aAlexander von Humboldt, quién los envió a Hippolyte VictorCollet-Descotils en París para su análisis. Collet-Descotils analizólas muestras e informó, equivocadamente, que contenía sólocromo por lo que von Humboldt, a su vez, rechazó la pretensión desu amigo Don Andrés sobre un nuevo elemento.

En 1830 en Suecia, el profesor Nils Gabriel Sefström lo redescubrióy lo bautizó con su nombre definitivo: vanadio, en homenaje aVanadis, la diosa escandinava de la belleza y el amor. En el mismoaño, Friedrich Wöhler, el químico alemán que sintetizó la urea porprimera vez, demostró, analizando muestras del mismo mineralestudiado por Don Andrés, que vanadio y eritronio eran el mismoelemento. Posteriormente, el geólogo estadounidense GeorgeWilliam Featherstonhaugh propuso, sin éxito, que el nuevoelemento fuese llamado rionio en honor a su descubridor original.Don Andrés comentó irónico frente al despojo: “el uso, que es tiranode las lenguas, ha querido que se llame vanadio, por no se quedivinidad escandinava; más derecho tenía otra mexicana, que ensus tierras se halló hace treinta años”. Finalmente el químico inglésHenry Enfield Roscoe lo aisló en forma pura, por primera vez, en1867. El último esfuerzo sin éxito por cambiar el nombre delelemento lo realizaron el físico mexicano Manuel Sandoval Vallarta yel historiador Arturo Arnaiz y Freg ante la Comisión Internacional deNomenclatura Química, en 1948.

Page 19: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 59

Page 20: Sir William Ramsay - uom.uib.catuom.uib.cat/digitalAssets/215/215961_1b.pdf · called wolfram, and the chemical symbol is taken from this name; in naming compounds of tungsten, use

10/10/12 Lliçó 0 60