WorksheetsHalf-Life
Total questions: 10
Worksheet time: 42mins
If you change external conditions (i.e. temperature, pressure, etc.) the half-life of a substance will
Increase
Decrease
Stay the same
If 10.0 mg of iodine-131 is given to a patient, how much is left after 24 days? The half-life of iodine-131 is 8 days.
1.25 mg
2.50 mg
5.00 mg
10.0 mg
The half-life of strontium-90 is 25 years. How much strontium-90 was originally present if 0.25 g is present in a sample after 100 years?
4.0 g
2.0 g
0.13 g
0.25 g
You have 100 grams of radioactive C-14. The half-life of C-14 is 5730 years. How many grams are left after 1 half-life?
100 grams
25 grams
2 grams
50 grams
After 4 half-lives, 1.0 g of a sample of Krypton-85 remains. What was the original mass of the sample?
16 g
32 g
0.063 g
0.25 g
What is the half-life of this isotope?
3 days
5 days
8 days
10 days
The half-life of Zn-71 is 2.4 minutes. If you had 100. g to start, how many grams would you have left after 7.2 minutes has elapsed?
100. g
50.0 g
12.5 g
8.50 g
Barium-122 has a half-life of 2 minutes. A fresh sample weighing 80.0 g was obtained. If it takes 10 minutes to set up an experiment using barium-122, how much barium-122 will be left when the experiment begins?
0.250 g
2.50 g
25.0 g
80.0 g
