Question

Of the thousands of different isotopes known to exist (select all that apply)

1)most are radioactive

2)only a few can be used to build an atomic bomb

3)some are used in medical diagnosis and treatment

4)none occur naturally

5)all of the above

Answer 1

option 1 is incorrect. Naturally occuring isotopes usually stables down to a non radioactive isotope The fraction of radioisotopes is very less.

option 2 is correct. The isotopes of Uranium-235 and Plutonium-239 were used because they readily undergo fission.

option 3 is correct.The diagnostic techniques in nuclear medicine uses radioactive tracers which are generally short-lived isotopes linked to chemical compounds which permit specific physiological processes to be scrutinised.

option 4 is inccorect. Many isotopes occurs naturally.

option 5 is incorrect. Since only 2 and 3 is correct.

Option 2 and option 3 are correct.