Mendelevium is a man made chemical element.
Mendelevium is an artificial, man made chemical element.
Mendelevium can be found only in rare specialized laboratories.
Yes, mendelevium is man made and radioactive.
Many isotopes have 148 neutrons; example: mendelevium -249.
It is a natural element.
Mendelevium.
Selenium is a natural element.
No it is not.
Lanthanum is a natural element.
Actinium is a natural chemical element, it is not a man-made element.
Argon is a natural element found in the air.
No, Uranium is naturally occurring. But all elements beyond uranium are man-made.