The amount of time it takes for some of the nuclei in a sample of the isotope to decay
The amount of time it takes for half the electrons in a sample of the isotope to decay
The amount of time it takes for half the nuclei in a sample of the isotope to decay
the amount of time it takes to double the nuclei in a sample of the isotope to decay
2. Multiple Choice
1 minute
1 pt
The half-life of Zn-71 is 2.4 minutes. If one had 100.0 g at the beginning, how many grams would be left after 7.2 minutes has elapsed?
100.0g
50.0g
12.5g
8.5g
3. Multiple Choice
2 minutes
1 pt
After the third half-life, how much of the sample is left?
1/2
1/3
1/16
1/8
4. Multiple Choice
15 minutes
1 pt
The half life of iodine-131 is 8.040 days. What percentage of an iodine-131 sample will remain after 40.20 days?
312.5%
31.25%
.3125%
3.125%
5. Multiple Choice
30 seconds
1 pt
Barium-122 has a half-life of 2 minutes. A fresh sample weighing 80 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?
0.25g
2.5g
25g
80g
6. Multiple Choice
15 minutes
1 pt
The half-life of strontium-90 is 25 years. How much strontium-90 will remain after 100 years if the initial amount is 4.0 g?
3.0g
0.25mg
0.3g
0.25g
7. Multiple Choice
30 seconds
1 pt
How many protons does U 235 atom have ?
235
92
143
67
8. Multiple Choice
30 seconds
1 pt
The radiation detected from a piece of rock is reduced significantly when the rock is wrapped in foil. What type of radiation is being emitted?
Alpha
Beta
Gamma
none of the above
9. Multiple Choice
30 seconds
1 pt
The beta particle has a charge of ...........
+1
-1
-2
+4
10. Multiple Choice
30 seconds
1 pt
Uranium-238 decays into Thorium-234 by emitting .........
an alpha particle
a beta particle
gamma rays
visible light
11. Multiple Choice
30 seconds
1 pt
Which type of nuclear radiation is being emitted here?
alpha
beta
gamma
none
12. Multiple Choice
30 seconds
1 pt
Nuclear fission is when scientists put atoms together.
True
False
13. Multiple Choice
30 seconds
1 pt
Gamma rays damage human cells/tissue.
True
False
14. Multiple Choice
30 seconds
1 pt
When nuclei decay, massive amounts of __________ is released.
energy
jello
protons
neutrons
15. Multiple Choice
30 seconds
1 pt
When an element loses protons, its __________changes.
protonic number
electronic number
neutronic number
atomic number
16. Multiple Choice
30 seconds
1 pt
What is this sketch showing?
Nuclear fusion
Nuclear action
Nuclear chain
Nuclear chain reaction
17. Multiple Choice
30 seconds
1 pt
What makes an element radioactive?
When it's nuclei expands
When it's electrons explode
When it's nuclei behave
When it's nuclei decay
18. Multiple Choice
30 seconds
1 pt
This is when scientists split the nuclei of atoms with neutrons.