Radioactive Decay

Question 1

How do you get the radioactivity constant from half life?

Answer 1

ln2/T

Question 2

What is the radioactivity constant?

Answer 2

The probability in a unit time that a nucleus will decay

Question 3

What is carbon dating?

Answer 3

A method to find the age of carbon-based materials that originated from living organisms

Question 4

How does carbon dating work?

Answer 4

All living things contain carbon, so when a living thing dies, it stops taking in carbon and has a predictable ratio of C12 to C14. The C14 starts to decay and the age can be estimated by comparing the activity of the dead thing compared to its equivalent living thing. Or the ratio of C14 to C12 can be used

Question 5

What are the limitations of carbon dating?

Answer 5

It assumes a constant ratio of C14 to C12 in the atmosphere (not true due to fossil fuel emissions)

Activities measured from tiny amounts of C14 are very small, and could be indistinguishable over background radiation

Question 6

What is an isotope?

Answer 6

Atoms of an element with the same number of protons but a different number of neutrons

Question 7

Which type of radiation is most ionising?

Answer 7

Alpha radiation