Radioactive Decay

2.2kg of Lead-198 was left on a park bench for 8 hours. How much was left? (half-life=2.4 hours)

Mathematical Equivalence

ON

100g of Flourine-17 was found in a shoe. If the material had been there for 5 minutes, how much was originally there? (in kg). (Half life=1.07minutes)

Mathematical Equivalence

ON

Determine the average mass after 80 seconds.

Determine the absolute uncertainty in mass after 120 seconds.

Match the following terms to their definitions

• Where unstable nuclei split to become smaller nuclei

• Radioactive Decay

• thermal energy transfer necessary to raise the temperature of 1kg of a substance by 1 degree

• Half-Life

• The time taken for half the atoms in a material to undergo radioactive decay

• Specific Heat Capacity

• heat required to complete a phase change

• Latent Heat

Use the graph to predict the half life of Flourine-17

350g of Gold-126 was left for 20 days in a lunchbox and decayed to 37 grams. Determine the half-life of the substance. (answer in days)

Mathematical Equivalence

ON

Identify the relationship between remaining mass and time. Use evidence from the graph to support your answer.

Infer the amount of substance left after 250 seconds. Justify your answer.