Manganese - a Brittle Metal

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Photo Credit: PeriodicTable.com
Atomic Number: 25
Relative Atomic Mass: 54.9
Group: 7
Period: 4
Block: D

Symbol: Mn

Manganese (which is photographed left) is a silver solid but brittle metal which is the fifth most abundant metal within the Earth crust. In the photo, the metal has been made into slabs by electroplating (using an electric current to coat another surface with the one you want) manganese out of a solution. Manganese minerals are widely distributed across Earth with pyrolucite (a black ore) and rhodochrosite (manganese carbonate, MnCO₃) being the most common minerals available.

Manganese can be found in the ocean. These sources of manganese are 24% manganese.

Discovery of Manganese

Manganese was discovered in the year 1774 by the Swedish chemist, a student at the time and keen metallurgist, Johann Gottlieb Gahn. A metallurgist is a scientist who is concerned with the branch of science and technology about the properties of metals. This includes the production of the metal along with how pure the metal is and Johnn Gahn wasn't the only person who helped with the isolation of manganese.
This is pyrolucite - MnO₂
Photo Credit: Wikipedia
In pre-historic times, manganese as the form of pyrolucite (shown in the photo: left), a black ore or manganese dioxide (MnO₂). This compound was used in cave paintings across the Lascaux caves, a settlement located in Southern France. The Lascaux caves are near the village of Montignac (or close to the city of Bordeaux). These cave paintings are 30,000 years old and are based on the typical local animals (fauna) around the caves during these creations were made.
In more modern times, the black ore was used by glass makers in order to remove the green tilt from the glass.

In 1940, Johann Heinrich Pott - a Belgian glass technologist, investigated the black ore chemically. Pyrolucite was shown to have no iron which had been assumed for some time. He instead was able to make potassium permanganate (PMnO₄) which is one of the strongest oxidising agents known.
In chemistry, an oxidising agent is a substance that has the ability to oxidise or cause another substance to lose their electrons. Other oxidisers that we have are Oxygen, hydrogen peroxide (H₂O₂) and any of the halogen elements (Fluorine, Chlorine, Bromine, Iodine).
This is Johann Gottlieb Gahn,
Photo Credit: Wikipedia

 In the 1700s, several chemicals tried to separate Manganese from the black ore - Pyrolucite. But, all of the chemists had been unsuccessful until this point. That was when the Swedish chemist and metallurgist, Johann Gottlieb Gahn successfully isolated the metal in 1774. He used Carbon to reduce pyrolucite to Manganese. 
Although, there was a student named Ignatius Kaim who was based in Vienna, Austria. Ignatius had already discovered Manganese. In his dissertation, written in 1771, Ignatius had described how he had produced the metal. 

The official records have Johann Gottlieb Gahn as the chemist who isolated.

 Now, manganese is mined from countries such as China, Africa, Australia and Gabon. The metal is then isolated from the sources by reducing the oxide (MnO₂) with other metals like Sodium, Magnesium or Aluminum. They can also use the process electrolysis to isolate manganese sulfate.

Biological Uses
These are my plants, they are growing on a window.
A spinach plant, a radish plant and marigolds. 
They too require Manganese - the compost contains that 

Manganese does have a biological role - it is essential for all living organisms as many enzymes contain this element. In particular, plants have an enzyme that has four atoms of manganese. This enzyme is used to break down water (H₂O) molecules into Oxygen and Hydrogen elements. Then the Oxygen would be used photosynthesis.
There are other enzymes in plants which has manganese in the makeup. Some enzymes are used in Nitrogen metabolism, synthesis of other elements as well as chloroplast formation.

Soils can have really low levels of Manganese in its makeup. So in order to grow certain plants, manganese is added to fertilisers. It can be also given to animals as a food supplement. 

The average human body contains about 12mg of manganese. Every day, we consume 4mg of manganese though eating types of food like nuts, bran, wholegrain cereal, tea and parley. 
You couldn't live without having manganese in your diet. A lack of manganese causes spongey bones and therefore, breaks easier. Plus, manganese was also essential for the production of vitamin B.

It's Uses
  • Manganese is too brittle to be used as a pure metal
    • Therefore, it is used as an alloy
  • Steel contains around 1% of manganese
    • It increases the strength of the compound
    • It improves the workability and resistance to wear
  • Manganese steel contains up to 13% manganese
    • This means that the compound is extremely strong 
    • This steel is used for railway tracks, safes, rifles and prison bars.
  • Drink cans also contain manganese - 1.5%, mixed with Aluminium
    • It improves the can's resistance to corrosion.
  • Manganese is also used as the formation of a mineral
    • Manganese (IV) Oxide (MnO₂) is used as the catalyst to remove the green tint from glass
    • Manganese sulfate (MnSO₄⋅H₂O) is used as a fungicide

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