All or almost all elements have radioactive isotopes if artificial isotopes are included. Among the naturally occurring elements, uranium, polonium, radium, and thorium have naturally occurring radioactive isotopes on earth.
Thulium is a non-radioactive element. It is part of the lanthanide series on the periodic table and has no stable isotopes that are radioactive. Thulium-169, the most common isotope, is stable and does not undergo radioactive decay. Therefore, thulium is considered non-radioactive.
The most radioactive element in the transition metals group is technetium. It has no stable isotopes and is typically produced in nuclear reactors as a byproduct. Its most common radioactive isotope is technetium-99, which is used in various medical procedures such as imaging scans.
The lanthanide and actinide series. Trait of lanthanide: Lanthanum, element 57. Trait of actinide: actinium, element 89.
Polonium is the element in group 16 that has unstable isotopes. It is a radioactive element with no stable isotopes.
All the isotopes of uranium are radioactive and unstable.
Promethium is a transition element. It is the only element in the lanthanide series that is radioactive and does not occur naturally on Earth. Its atomic number is 61, and it is commonly used in nuclear batteries and research applications.
Thulium is a non-radioactive element. It is part of the lanthanide series on the periodic table and has no stable isotopes that are radioactive. Thulium-169, the most common isotope, is stable and does not undergo radioactive decay. Therefore, thulium is considered non-radioactive.
There is no group specified so it is not possible to be sure about this answer but all isotopes of promethium are radioactive.
Plutonium is an actinide
The bottom two rows of Lanthanide & Actinide is the transition metals
The most radioactive element in the transition metals group is technetium. It has no stable isotopes and is typically produced in nuclear reactors as a byproduct. Its most common radioactive isotope is technetium-99, which is used in various medical procedures such as imaging scans.
The lanthanide and actinide series. Trait of lanthanide: Lanthanum, element 57. Trait of actinide: actinium, element 89.
These isotopes are unstable and disintegrate emitting radiations.
Polonium is the element in group 16 that has unstable isotopes. It is a radioactive element with no stable isotopes.
Pm is Prometheum. All isotopes of this element are radioactive.
Simply by being radioactive or not. An isotope is an atomic variant of the same element, and has the same chemical characteristics, but is not necessarily radioactive.
An example is uranium.