Absolute Dating

Question 1

Which statement accurately describes radioactive dating?

Revolt · Accepted Answer

Geologist compare the observed abundance of naturally occurring radioactive isotopes and their decay products using decay rates.

Question 2

Study the diagram of radioactive decay.

Revolt · Accepted Answer

energy and particles

Question 3

The graph shows calculations for potassium-argon dating.

Revolt · Accepted Answer

They can determine that a rock is 1.3 billion years old if 1/2 of the potassium has decayed.

Question 4

Which phrase describes one characteristic of radioactive elements?

Revolt · Accepted Answer

decay at a constant rate

Question 5

How is radioactive decay used to date sedimentary rocks?

Revolt · Accepted Answer

The amounts of unstable elements in the volcanic layers above and below the sedimentary layers are measured.

Question 6

What is the age of a meteorite if potassium-40 decayed from 80 g to 10 g? The half-life of potassium-40 is 1.3 billion years.

Revolt · Accepted Answer

3.9 billion years

Question 7

Which statement explains why carbon-14 dating cannot be used to date ancient rocks?

Revolt · Accepted Answer

Carbon-14 decays quickly leaving the amount too small to measure.

Question 8

Which phrase describes the element carbon-14?

Revolt · Accepted Answer

found in an organism’s remains

Question 9

The chart shows rate of decay.

Revolt · Accepted Answer

amount of material that has not decayed

Question 10

Which property of argon makes it useful for potassium-argon dating?

Revolt · Accepted Answer

It remains trapped in rock.

Absolute Dating Answers