Which property of argon makes it useful for potassium-argon dating? a. it decays into potassium. b. it is an unstable element. c. it remains trapped in rock. d. it is useful only for dating newer rock.

Potassium-argon dating:-

Potassium-argon dating method is used for dating of very old archaeological rocks. Geologist are using this method of dating for rocks as old as 4 billion years old. This method is based on calculation of the product of the radioactive decay of an isotope of potassium (K) into argon (Ar). Argon which is a noble gas, is a minor component of rock sample of geographical inyterest . When K decays to A r, it tremain trapped within the lattice as it is larger than the sapces between the other atoms in a crystal .

So the answer is C. It remains trapped in rock, this property of argon that is Ar make it useful for dating.

C

Explanation:

they are all solids.