No student devices needed. Know more
21 questions
Imagine you have 50,000 atoms of uranium-238. If U-238 has a half-life of 4.5 billion years, how many U-238 atoms will be left after 4.5 billion years?
25,000
50,000
12,500
0
What is the Half Life of this isotope?
3 days
5 days
8 days
10 days
What is the Half life of this isotope?
5 seconds
10 seconds
15 seconds
20 seconds
The diagram shows 32 atoms.
16 of the Red are parent isotopes
16 of the Green are daughter isotopes
How many half-lives have occurred?
0
1
2
3
The diagram shows 32 atoms
32 of the Red are the parent isotope
0 of the atoms are daughter isotopes
How many half-lives have occurred?
0
1
2
3
The % of the parent isotope remaining after 2 Half Lives.
50%
25%
12.5%
6.25%
The % of the parent isotope remaining after 1 Half Life.
50%
25%
12.5%
6.25%
After 22,800 years, approximately what percentage of the original carbon-14 remains?
15%
12.5%
6.25%
3.125%
A nuclear reaction occurs when the atom is
ready to give away electrons
stable
in need of electrons
unstable
The largest radioactive particle that can be stopped by your skin is called a(n)
positron
beta particle
alpha particle
gamma particle
The smallest and highest energy type of nuclear radiation is known as a(n)
alpha particle
beta particle
gamma particle
positron
A scientist detected radiation escaping from a material encased in a thin metal box. What type of radiation did the scientist most likely detect?
alpha particles
beta particles
gamma particles
positrons
All radioactive sources have a half-life.
Which statement about the half-life of a source is correct?
It is half the time it takes for an atom to decay
It is the length of time it takes for half of the original amount of the radioisotope to decay to another element.
It is half the time for the radioactive source to become safe
It is half the time it takes the activity of the source to decrease to zero
Can be stopped by aluminum foil; has no mass and negative charge.
beta particle
alpha partcle
gamma ray
half-life
Powerful radiation that can cause biological damage.
beta particle
alpha particle
gamma ray
carbon dating
The half-life of Pu-239 is 5 minutes. How much of a 200g sample is left after 20 minutes?
25g
180g
12.5
4g
What process is used to make energy in nuclear power plants?
fusion
oxidation
fission
combustion