This is a special metal. 
This is a special metal. 
It is a silvery gray color. A long time ago, a scientist saw a gap in his chart. He knew a metal was missing. He even guessed what it would be like!
Later, people made this metal in a lab. It is called technetium. It is the first metal made by people.
This metal is very helpful. Doctors use it to look inside the body. It can help find sickness in bones.
We also found this metal in far away stars. This shows that stars can make new things. It is a very busy metal!
Technetium is a silvery-gray metal. 
A long time ago, a scientist named Dmitri Mendeleev studied the elements. He saw a gap in his chart. He predicted a missing metal would fit there. He called it eka-manganese.
In 1937, scientists finally made this metal. They made it in a lab. This made it the first man-made element. Its name comes from a Greek word. That word means "artificial."
Technetium is radioactive. This means it gives off power. Most technetium is made by people. It can also be found in tiny amounts in nature. It comes from uranium ore.
This metal helps doctors every day. They use a type called technetium-99m. It helps them see inside the body. It can find bone cancer. 
Scientists also found technetium in far-off stars. This was a big discovery. It proved that stars make heavy elements. This happens through nuclear reactions. 
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. 

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.
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. 
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. 
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. 
Technetium is a unique chemical element with the symbol Tc and atomic number 43. It is a silvery-gray, crystalline transition metal. This metal is quite unusual because it is the lightest element whose isotopes are all radioactive. In the periodic table, it is located in group 7. This placement puts it between manganese and rhenium. Because of this position, its chemical properties are intermediate between those two neighbors. 
Technetium is primarily a synthetic element. This means most of it is produced by humans in a laboratory rather than being found in large amounts in nature. One way it is made is through the fission of uranium-235 in nuclear reactors. Scientists extract long-lived isotopes from the resulting nuclear fuel rods. However, small amounts do occur naturally. It can be found in uranium or thorium ores as a spontaneous fission product. It can also form in molybdenum ores through a process called neutron capture.
The history of discovering technetium is filled with many attempts and errors. In the 1860s, Dmitri Mendeleev noticed a gap in his periodic table. He predicted a missing element existed between molybdenum and ruthenium. He gave this predicted element the provisional name eka-manganese. Many researchers claimed to find the element before it was officially discovered. They often misidentified other materials like iridium or niobium. In 1925, Walter Noddack, Otto Berg, and Ida Tacke reported finding element 43. They called it masurium, but other scientists could not replicate their results.
The official discovery finally happened in 1937. Carlo Perrier and Emilio Segrè confirmed the element at the University of Palermo in Sicily. They used a molybdenum foil that had been made radioactive in a cyclotron. This machine is a type of particle accelerator. By using comparative chemistry, they proved the activity came from element 43. Because it was the first element produced artificially, it was named technetium. This name comes from the Greek word for artificial. 
Technetium has very important uses in modern medicine. One specific version is called technetium-99m. This is a short-lived nuclear isomer that emits gamma rays. Doctors use it in nuclear medicine for many different diagnostic tests. For example, it is used to help diagnose bone cancer. This isotope is used in about ten million medical procedures every year. It is a vital tool for seeing how the body is working. 
This element also helped scientists understand the life of stars. In 1952, astronomer Paul W. Merrill detected technetium in the light of red giants. Red giants are stars that are near the end of their lives. Because technetium is short-lived, its presence in these stars was a major discovery. It proved that stars can produce heavier elements through nuclear reactions. This process is known as nucleosynthesis. This finding helped confirm that stars act as factories for the elements in our universe.
Technetium also shows interesting physical and chemical behaviors. As a metal, it is slightly paramagnetic. This means its magnetic dipoles align when a magnetic field is applied. Pure single-crystal technetium can also become a type-II superconductor. This happens when it is cooled below a very low temperature. Chemically, it can form many different types of compounds. One common form is sodium pertechnetate, which is used in various applications. 
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