Question

Which of the following radioisotopes is naturally occurring?

93^239Np

53^131I

102^254No

96^242Cm

Answer 1

I - 131 is the correct answer.

I - 131 is the only naturally occuring radioactive isotope among these four options.

Step-by-step explanation:

Np - 239 - Neptunium is also considered as an artificial element,as only trace amounts of it are found in nature.

And Np - 239 is not a naturally occuring radioactive isotope but it is synthesized artificially.

No - This is an artificial element.That means its not found in nature. Hence all its isotopes are also synthesized artificially.

Cm - This is also an artificial element and all its isotopes are also synthesized artificially.

Np - 239,No - 254,Cm - 242 are radioactive isotopes but they are not naturally occuring radioactive isotopes. But these three are artificially made radioactive isotopes.

And Iodine - 131 is the only naturally occuring radioisotope among these.

Answer 2

The answer is 53^131I.

This is a radioisotope of iodine. It also has a radioactive half life decay of about 8 days.