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Technetium

physical science Maturity 11-13 Next article →

Technetium is a unique silvery-gray metal. It sits in group 7 of the periodic table. This means it is located between manganese and rhenium.

Periodisches System der Elemente (1904-1945, now Gdansk University of Technology)
Periodisches System der Elemente (1904-1945, now Gdansk University of Technology)

Its chemical properties are in the middle of those two neighbors. Technetium is also a transition metal. It has a crystalline structure. It is the lightest element whose isotopes are all radioactive. This radioactivity makes it very special to study.

Zirconium-tetrachloride-3D-balls-A
Zirconium-tetrachloride-3D-balls-A

Most technetium is made by people in a lab. This is called being a synthetic element. It can be made by using a machine called a cyclotron. Scientists can also find it in nature in very tiny amounts. It appears in uranium ore or thorium ore. It also comes from molybdenum ores through neutron capture.

Pertechnetate1
Pertechnetate1

In nuclear reactors, it is a byproduct of uranium-235 fission. These long-lived isotopes are then extracted from fuel rods. This way of making it helps us understand how atoms work.

Long ago, a scientist named Dmitri Mendeleev saw a gap. He looked at his periodic table in the 1860s. He noticed a space between molybdenum and ruthenium. He predicted a missing element would fit there. He called it eka-manganese.

Basedow-vor-nach-RIT
Basedow-vor-nach-RIT

Many researchers tried to find it before it was official. Some thought they found it, but they were wrong. In 1937, Carlo Perrier and Emilio Segrè finally confirmed it. They used a molybdenum foil from a cyclotron. This discovery was very important for science history.

Technetium has many interesting numbers and facts. Its atomic number is 43. Its chemical symbol is Tc. One common isotope is called technetium-99. Another version is technetium-99m. This version is a short-lived nuclear isomer. It is used in ten million medical tests every year.

First technetium-99m generator - 1958
First technetium-99m generator - 1958

Doctors use it to find things like bone cancer. It is a very helpful tool in nuclear medicine. It helps doctors see inside the human body.

This metal also tells us secrets about outer space. In 1952, an astronomer named Paul W. Merrill found it in stars. He saw its signature in light from red giants. These stars are near the end of their lives.

Basedow-vor-nach-RIT
Basedow-vor-nach-RIT

Finding it there proved that stars create heavy elements. This happens through a process called nucleosynthesis. It shows that stars are like giant factories for elements. This connects the tiny atoms in a lab to the huge stars in the sky.

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🖼️ Images & Media (7)
File:Periodisches System der Elemente (1904-1945, now Gdansk University of Technology).jpg
Periodisches System der Elemente...
File:Pertechnetate1.svg
Pertechnetate1.svg
File:Zirconium-tetrachloride-3D-balls-A.png
Zirconium-tetrachloride-3D-balls-A.png
File:Chloro-containing coordination complexes of technetium (Tc-99).jpg
Chloro-containing coordination complexes...
File:Tc CNCH2CMe2(OMe) 6Cation.png
Tc CNCH2CMe2(OMe) 6Cation.png
File:First technetium-99m generator - 1958.jpg
First technetium-99m generator - 1958.jpg
File:Basedow-vor-nach-RIT.jpg
Basedow-vor-nach-RIT.jpg
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