Absolute Age

Question 1

What is absolute age used for?

Answer 1

To determine the actual (numerical) age of the rock

Question 2

What is used to find the absolute age of something?

Answer 2

Certain elements that experience radioactive decay

Question 3

Radioactive decay:

Answer 3

The spontaneous and natural breakdown from unstable to stable atomic forms

Question 4

What happens during the radioactive decay process?

Answer 4

Energy is released

Question 5

Describe the radioactive decay process.

Answer 5

The process has a constant and predictable rate unaffected by the environmental changes

Question 6

Radioactive isotope:

Answer 6

The unstable form of an element which has a different number of neutrons in their atomic nucei

Question 7

Decay product:

Answer 7

When a radioactive isotope breaks down to a stable form, it creates what is known as a decay product

Question 8

Half-life:

Answer 8

The time it takes a radioactive isotope to decay to half of its original amount

Question 9

Half-life occurs at a ___ rate:

Answer 9

Predictable

Question 10

Radioactive isotopes: Carbon-14:

Answer 10

• Decays into N-14
• Used to date once living things
• Can be used to date things as old as 54,000 years
• After 54,000 years there isn’t enough C-14 left to accurately date the object

Question 11

Radioactive isotope: Potassium-40:

Answer 11

• K-40 decays into stable Ar-40 & Ca-40
• Used for rocks & fossils
• Used for old objects-> 1,300,000,000

Question 12

Radioactive isotope: Uranium-238:

Answer 12

• U-238 decays into stable Pb-206

- Used to date very old rock and very old fossils up to and over 4,600,000,000

Question 13

Radioactive isotope: Rubidium-87:

Answer 13

• Rb-87 decays in to Strontium-87

- Used to date extremely old rock and extremely old fossils