3.1 Extracting Metals: Reduction
Some metals are so unreactive that they are found in the earth as metals. Examples, include gold and silver. However, most metals are found as compounds that require extraction. These compounds are known as ore. Ores are mined from the ground and must contain enough metal to make it economically worthwhile extracting. Over time the economics of extracting metal may change as technology advances are making it cheaper to extract metals from ores. This may make it financially viable to extract metal from ore with a lower concentration of metal. Also, if the price of a metal was to increase, it would make it viable to extract metals from ores with less of the metal in. Alternatively, if the price of a metal was to fall, then some of the ores that are being mined now may not be economically viable.
The ore will be mined out of the ground. An ore may be concentrated before it is extracted and purified. Concentrating is the process of getting rid of the unwanted materials in the ore, such as rocks that have little or no metal in them. This makes the extraction process costly meaning that we do not want to extract metal from material that has little or none of the metal that we desire.
There are two ways that a metal can be extracted from its ore; reduction and electrolysis. The method used for extraction is dependent on how reactive the metal is. The table below shows some metals and how reactive they are.
The ore will be mined out of the ground. An ore may be concentrated before it is extracted and purified. Concentrating is the process of getting rid of the unwanted materials in the ore, such as rocks that have little or no metal in them. This makes the extraction process costly meaning that we do not want to extract metal from material that has little or none of the metal that we desire.
There are two ways that a metal can be extracted from its ore; reduction and electrolysis. The method used for extraction is dependent on how reactive the metal is. The table below shows some metals and how reactive they are.
All the metals that are more reactive than carbon need to be extracted using electrolysis. Metals that are less reactive than carbon can be extracted by reduction. Carbon is used in the reduction process and can only take oxygen away from metals that less reactive than itself.
Reduction
Reduction is the removing of oxygen from a substance (an ore) through a chemical reaction that uses carbon. Carbon reacts with the oxygen in the ore, resulting in carbon dioxide and the desired metal. Let’s take iron oxide. Using carbon to take away the oxygen gives us pure iron, which can be used to produce goods.
Reduction is the removing of oxygen from a substance (an ore) through a chemical reaction that uses carbon. Carbon reacts with the oxygen in the ore, resulting in carbon dioxide and the desired metal. Let’s take iron oxide. Using carbon to take away the oxygen gives us pure iron, which can be used to produce goods.