Q. Consider the following statements:
- The most abundant isotope of carbon in the atmosphere is C-14.
- The ratio of C-12 to C-14 in the atmosphere is almost static, and is known.
Which of the statements given above is/are correct?
Answer:
Only 2
Notes:
- Carbon dating is a widely-used method to establish the age of organic materials, things that were once living.
- The most abundant isotope of carbon in the atmosphere is C-12.
- The ratio of C-12 to C-14 in the atmosphere is almost static, and is known.
- The Carbon Dating method cannot be used to determine the age of non-living things like rocks, for example.
- Also, the age of things that are more than 40,000-50,000 years old cannot be arrived at through carbon dating.
- This is because after 8-10 cycles of half-lives, the amount of C-14 becomes almost very small and is almost undetectable.
- While C-12 is stable, the radioactive C-14 reduces to one half of itself in about 5,730 years — known as its ‘half-life’.
- The changing ratio of C-12 to C-14 in the remains of a plant or animal after it dies can be measured and can be used to deduce the approximate time when the organism died.