Absolute Dating

Front

The length of time required for half of the radioactive atoms in a sample to decay is its...

Back

half-life

Front

How does absolute age differ from relative age?

Back

only absolute dating finds the age in years

Front

Radiometric dating is possible because the rates of decay of radioactive isotopes _____.

Back

are constant

Front

The time it takes for 50% of the nuclei in a radioactive sample to decay to its stable isotope is called _____

Back

the half-life

Front

If the half-life of a radioactive group of atoms is 100 years, then how old is the rock if there have been two half-lives?

Back

200 years

Front

What element is usually used to date fossils? Options: uranium-235, carbon-14, mercury-203, thorium-234

Back

carbon-14

Front

How old is the Earth?

Back

4.6 billion years

Front

The original element that undergoes radioactive decay is known as the...

Back

parent element

Front

If 10 mg of iodine 131 is given to a patient, how much is left after 24 days? The half-life of iodine-131 is 8 days.

Back

1.25mg

Front

The half-life of strontium-90 is 25 years. How much strontium-90 will remain after 100 years if the initial amount is 4.0 g?

Back

0.25g