Question 3

Which of the following isotopes is not commonly used for dating objects?

A) carbon-14

B) phosphorus-32

C) potassium-40

D) rubidium-87

Among all the given options Phosphorous-32 is not used for dating of objects.

Answer: B) phosphorus-32

Explanation:

In this question carbon-14 is the radioactive isotope used in carbon dating process which is employed to date the age of remains of organisms. Potassium-40 isotope is used in potassium-argon dating which is generally used to determine the age of old rocks.

Rubidium-87 is used in rubidium-strontium dating method. In this method rubidium-87 converts into strontium-87 by undergoing beta decay. Age of igneous and metamorphic rocks can be determined using this method.