1. Learning Objective:
I will be able to explain how we use half lives to determine the age of a rock.

2. Success Criteria:
I can use the ESRT to determine the half live of common radioisotopes.
I can correctly follow procedures to complete my lab.
I can graph the data collected.

3. When an unstable radioactive element changes into a stable element
Radioactive Decay
When an unstable radioactive element changes into a stable element

4. Example Unstable Radioactive Isotope Stable Decay Product
Carbon 14 (C14)
Nitrogen 14 (N14)
Uranium 238 (U238)
Lead 206 (Pb206)
Parent
Daughter

5. Radiometric Dating
Half life: The time required for 1/2 of a parent material to break down to daughter material

6. Radiometric Dating
The half lives of radioisotopes vary depending upon the isotope
Examples:
C14 = 5,770 years
U238 = 4,500,000,000 years
Rb87 = 47,000,000,000 years

7. Carbon 14 is used to date biological remains
Carbon is incorporated into the cells of living organisms and begins to decay when the organism dies
Uranium 238 is used to date rocks
Larger half life

8. If half the K -40 of a rock has decayed into Ar-40, how old is the rock?
How many years would it take for 75 % of a sample of K-40 to disintegrate?

9. Half Life M&M Lab
Learning Objective: I will be able to explain how we use half lives to determine the age of a rock.
Success Criteria:
I can use the ESRT to determine the half live of common radioisotopes.
I can correctly follow procedures to complete my lab.
I can graph the data collected.

10. A sample that has ½ c-14 and ½ n-14?
How old are:
A sample that has ½ c-14 and ½ n-14?
A sample that has ¼ K-40 and ¾ Ar-40?
A sample that has ½ U-238 ½ Pb-206?

11. How old are:
A sample that has 1/8 Rb-87 and 7/8 Sr-87?
A sample that has ¼ C-14 and ¾ N-14?
A sample that has ¾ C-14 and ¼ N-14?

12. What fraction remains of:
May 19
A 50 billion year old sample has ____ Rb-87 and ____ Sr-87.
A 2.6 billion year old sample has____ K-40 and ____Ar-40.
Allen

13. Stranz should take a break ;)
This is so boring
Stranz should take a break ;)