Tantalum is a greyish silver, heavy, and very hard metal.
When pure, it is ductile and can be drawn into fine wire, which can be used as
a filament for evaporating metals such as aluminium. Tantalum is almost
completely immune to chemical attack at temperatures below 150°C, and is
attacked only by hydrofluoric acid, acidic solutions containing the fluoride
ion, and free sulphur trioxide. The element has a melting point
exceeded only by tungsten and rhenium.
Table: basic information about and classifications of tantalum.
Table: basic information about and classifications of tantalum.
•Name:
Tantalum
•Symbol: Ta
•Atomic number: 73
•Atomic weight: 180.94788 (2)
•Standard state: solid at 298 K
•CAS Registry ID: 7440-25-7
•Group in periodic table: 5
•Group name: (none)
•Period in periodic table: 6
•Block in periodic table: d-block
•Color: grey blue
•Classification: Metallic
Historical information
Tantalum was discovered by Anders Gustaf Ekeberg at 1802 in Sweden, but many chemists thought niobium and tantalum were one and the same. Origin of name is from the Greek word "Tantalos" meaning "father of Niobe" (Greek mythology: According to Homer’s Iliad, she had six sons and six daughters and boasted of her progenitive superiority to the Titan Leto, who had only two children, the twin deities Apollo and Artemis. As punishment for her pride, Apollo killed all Niobe’s sons, and Artemis killed all her daughters Oh how pleasant those gods and goddesses...). Tantalum is closely related to niobium in the periodic table, so the names are fitting! Some felt that perhaps tantalum was an allotrope [coined from Greek words meaning "other" + "form") is the property of some chemical elements to exist in two or more different forms] of niobium. Later, Rose, in 1844, and Marignac, in 1866, showed that niobic and tantalic acids were two different acids.
The first relatively pure tantalum was produced by von Bolton in 1907.
Physical properties
•Melting point: 3290 [or 3017 °C (5463 °F)] K
•Boiling point: 5731 [or 5458 °C (9856 °F)] K
•Density of solid: 16650 kg m-3
Orbital properties
•Ground state electron configuration: [Xe].4f14.5d3.6s2
•Shell structure: 2.8.18.32.11.2
•Term symbol: 4F3/2
Isolation
Isolation of tantalum appears to be complicated. Tantalum minerals usually contain both niobium and tantalum. Since they are so similar chemically, it is difficult to separate them. Tantalum can be extracted from the ores by first fusing the ore with alkali, and then extracting the resultant mixture into hydrofluoric acid, HF. Current methodology involves the separation of tantalum from these acid solutions using a liquid-liquid extraction technique. In this process tantalum salts are extracted into the ketone MIBK (methyl isobutyl ketone, 4-methyl pentan-2-one). The niobium remains in the HF solution.
After conversion to the oxide, metallic tantalum can be made by reduction with sodium or carbon. Electrolysis of molten fluorides is also used.
•Symbol: Ta
•Atomic number: 73
•Atomic weight: 180.94788 (2)
•Standard state: solid at 298 K
•CAS Registry ID: 7440-25-7
•Group in periodic table: 5
•Group name: (none)
•Period in periodic table: 6
•Block in periodic table: d-block
•Color: grey blue
•Classification: Metallic
Historical information
Tantalum was discovered by Anders Gustaf Ekeberg at 1802 in Sweden, but many chemists thought niobium and tantalum were one and the same. Origin of name is from the Greek word "Tantalos" meaning "father of Niobe" (Greek mythology: According to Homer’s Iliad, she had six sons and six daughters and boasted of her progenitive superiority to the Titan Leto, who had only two children, the twin deities Apollo and Artemis. As punishment for her pride, Apollo killed all Niobe’s sons, and Artemis killed all her daughters Oh how pleasant those gods and goddesses...). Tantalum is closely related to niobium in the periodic table, so the names are fitting! Some felt that perhaps tantalum was an allotrope [coined from Greek words meaning "other" + "form") is the property of some chemical elements to exist in two or more different forms] of niobium. Later, Rose, in 1844, and Marignac, in 1866, showed that niobic and tantalic acids were two different acids.
The first relatively pure tantalum was produced by von Bolton in 1907.
Physical properties
•Melting point: 3290 [or 3017 °C (5463 °F)] K
•Boiling point: 5731 [or 5458 °C (9856 °F)] K
•Density of solid: 16650 kg m-3
Orbital properties
•Ground state electron configuration: [Xe].4f14.5d3.6s2
•Shell structure: 2.8.18.32.11.2
•Term symbol: 4F3/2
Isolation
Isolation of tantalum appears to be complicated. Tantalum minerals usually contain both niobium and tantalum. Since they are so similar chemically, it is difficult to separate them. Tantalum can be extracted from the ores by first fusing the ore with alkali, and then extracting the resultant mixture into hydrofluoric acid, HF. Current methodology involves the separation of tantalum from these acid solutions using a liquid-liquid extraction technique. In this process tantalum salts are extracted into the ketone MIBK (methyl isobutyl ketone, 4-methyl pentan-2-one). The niobium remains in the HF solution.
After conversion to the oxide, metallic tantalum can be made by reduction with sodium or carbon. Electrolysis of molten fluorides is also used.
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