Question

Which of the following is a radioactive

element?

A. Cobalt

B. Uranium

C. Argon

D. Chromium​

Answer 1

Answer:

Uranium ...

hope it helps you!!

Answer 2

Sol. • Uranium is weakly radioactive

because all its isotopes are unstable (with

half-lives of the five naturally known

isotopes, uranium-233 to uranium-236

and uranium-238, varying between

159200 years and 4.5 billion years).

• This radioactive metal is unique in that

one of its isotopes, uranium-235, is the

only naturally occurring isotope capable

of sustaining a nuclear fission reaction.