Tuesday, May 22, 2012

Blog 11.1 Table J and the Activity Series of Metals

Blog Questions:
  • The nitrate ion is known as a spectator ion because nitrate ion exists as a reactant and a product in the chemical equation and it doesn't participate in the reaction.
  •  In the reaction between magnesium and silver solution , Magnesium was oxidized and Silver was reduced.
Metal X wouldn't react with metal Y+2 because if a two metal system is set up, the higher up metal in table J will lose electrons to the lower metal ion.

The activity series given on table J, lists metals in order of decreasing reactivity. In each period on the reference table, metallic character of elements decreases as we move to the right. Element to the left have a pronounced metallic character while those to the right have a non-metallic character. Conversely, non-metallic character increases from left to right.

The Most reactive metals or nonmetals are on top of the chart in table J and the least active metals or non metals are in the bottom of the table.

Because gold, copper, and silver were discovered so long because they're the least active metal based on table J. The other were find later because those elements are above H2 are prone to oxidation in the air, and therefore unlikely to be found in pure form on the Earth's surface.

Copper ore was mixed with charcoal and Iron ore in a pit fumace. The Charcoal was fired to reduce the copper ore to copper. The iron ore formed a "slag" with e.g., the silica. It was a lucky happenstance that the Iron Ore and the Copper Ore occurred together. Without the iron ore to "flux" the slag, it would have been difficult to separate the liquid copper from the solid slag. After firing, the slag was drained off into a pit, and the copper was then removed from the furnace.

The copper and tin were melted in a crucible to form the bronze. The high temperatures were achieved using foot bellows to blow air into the fire. The foreman (inset) does his bit by stirring the melt to homogenize the bronze.

Enrichment:

In film developing, photographic developer (or just developer) is a chemical that makes
the latent image on the film or print visible. It does this by reducing the silver halides that have been exposed to light to metals of elemental silver in the gelatine matrix. As a generalization, the longer a developer is allowed to work the greater the degree of reduction of the silver halide crystals to silver and therefore the darker image.

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