Description : Which of the following elements is nonradioactive? (1) Uranium (2) Thorium (3) Plutonium (4) Zirconium
Last Answer : (4) Zirconium Explanation: Zirconium is non-radioactive. It is a chemical element with the symbol Zr, atomic number 40 and atomic mass of 91.224. The name of zirconium is taken from the ... important source of zirconium. It is a lustrous, grey-white, strong transition metal that resembles titanium.