1. Topic: Nuclear Chemistry
Aim: What is half-life, and what calculations can be performed with it?
Do Now: Write a full nuclear equation for the decay of K-37.
What is the half life of K-37?
HW:

2. Half-life The time it takes for ½ of a sample to decay (Table N)
What is the half-life of 16N?
7.2 seconds
What does this mean?
What is the half-life of 226Ra?
1600 years

3. Half Life Calculations
What is the question asking you to find?
What should the unit be for your answer? (Unit of time? Unit of mass?)
What data does the question give you?
What data can you look up?
What equation can you use?
Is there a shortcut?

4. You will be given 3 of 5 or 4 of 5 pieces of info in the problem.
HELP ME HELP YOU. R T H O F
Radioisotope (which one?)
Total time
Half life
Original amount
Final amount
You will be given 3 of 5 or 4 of 5 pieces of info in the problem.

5. Half-Life Calculations
A radioisotope has a half-life of 10 days. 1 gram remains after 40 days. What was the initial amount of the radioisotope?

6. Half-Life Calculations
100 grams of a radioisotope decayed to 12.5 grams after 90.7 years. What was the half-life?

7. Half-Life Calculations
131I has a half-life of 8.07 days. A 10 gram sample was allowed to decay for 32 days. What fraction will remain?

8. Sample Questions

9. Sample Questions

10. Sample Questions