Name: Caroline Sobolowski Date: 1/1/17
Student Exploration: Half-life
Vocabulary: daughter atom, decay, Geiger counter, half-life, isotope, neutron, radiation,
radioactive, radiometric dating
Prior Knowledge Questions (Do these BEFORE using the Gizmo.)
1. Have you ever made microwave popcorn? If so, what do you hear while the popcorn is in the
m
er as
microwave? Yes, I hear the kernels popping in the bag.
co
eH w
2. If you turn the microwave on for two minutes, is the rate of popping always the same, or does it
o.
rs e
change? Explain. The rate of popping is not always the same because when you first put
ou urc
the bag of popcorn in and start the microwave, there is not a lot of popping, but when the
o
contents of the bag begin to heat up, the popping increases. By the end of the cooking
aC s
session, all of the kernels should be popped so there is no more popping.
vi y re
Gizmo Warm-up
Like an unpopped kernel in the microwave, a radioactive
atom can change at any time. Radioactive atoms change
ed d
by emitting radiation in the form of tiny particles and/or
ar stu
energy. This process, called decay, causes the
radioactive atom to change into a stable daughter atom.
The Half-life Gizmo™ allows you to observe and measure
is
the decay of a radioactive substance. Be sure the sound
Th
is turned on and click Play ( ).
1. What do you see and hear? There is a static sort of popping sound as the atoms turn
from red to blueish gray.
sh
Note: The clicking sound you hear comes from a Geiger counter, an instrument that detects
the particles and energy emitted by decaying radioactive atoms.
This study source was downloaded by 100000793680026 from CourseHero.com on 06-25-2021 06:12:18 GMT -05:00
https://www.coursehero.com/file/18657578/Half-lifeGizmo/
, 2. What remains at the end of the decay process? Daughter Atoms
3. Is the rate of decay fastest at the beginning, middle, or end of the process? The rate of
decay is fastest near the beginning.
Get the Gizmo ready:
Activity A: ● Click Reset ( ). Be sure that User chooses
half-life and Random decay are selected.
Decay curves ● Check that the Half-life is 20 seconds and the
Number of atoms is 128.
Question: How do we measure the rate of radioactive decay?
1. Observe: Select the BAR CHART on the right side of the Gizmo and click Play.
A. What happens to the numbers of radioactive and daughter atoms as the simulation
m
er as
proceeds? The number of radioactive atoms decreases until they reach zero
co
eH w
and the number of daughter atoms increases.
o.
rs e
B. Do the numbers of radioactive and daughter atoms change at the same rate
ou urc
throughout the simulation? Explain. No, the numbers of daughter atoms increase
o
steadily while towards the end of the reaction, the radioactive atoms take
aC s
vi y re
longer to disappear.
2. Experiment: Click Reset, and select the GRAPH tab. Run a simulation with the Half-life set
ed d
to 5 seconds, and then run another simulation with the Half-life set to 35 seconds. Sketch
ar stu
each resulting decay curve graph in the spaces below.
is
Th
sh
This study source was downloaded by 100000793680026 from CourseHero.com on 06-25-2021 06:12:18 GMT -05:00
https://www.coursehero.com/file/18657578/Half-lifeGizmo/
Student Exploration: Half-life
Vocabulary: daughter atom, decay, Geiger counter, half-life, isotope, neutron, radiation,
radioactive, radiometric dating
Prior Knowledge Questions (Do these BEFORE using the Gizmo.)
1. Have you ever made microwave popcorn? If so, what do you hear while the popcorn is in the
m
er as
microwave? Yes, I hear the kernels popping in the bag.
co
eH w
2. If you turn the microwave on for two minutes, is the rate of popping always the same, or does it
o.
rs e
change? Explain. The rate of popping is not always the same because when you first put
ou urc
the bag of popcorn in and start the microwave, there is not a lot of popping, but when the
o
contents of the bag begin to heat up, the popping increases. By the end of the cooking
aC s
session, all of the kernels should be popped so there is no more popping.
vi y re
Gizmo Warm-up
Like an unpopped kernel in the microwave, a radioactive
atom can change at any time. Radioactive atoms change
ed d
by emitting radiation in the form of tiny particles and/or
ar stu
energy. This process, called decay, causes the
radioactive atom to change into a stable daughter atom.
The Half-life Gizmo™ allows you to observe and measure
is
the decay of a radioactive substance. Be sure the sound
Th
is turned on and click Play ( ).
1. What do you see and hear? There is a static sort of popping sound as the atoms turn
from red to blueish gray.
sh
Note: The clicking sound you hear comes from a Geiger counter, an instrument that detects
the particles and energy emitted by decaying radioactive atoms.
This study source was downloaded by 100000793680026 from CourseHero.com on 06-25-2021 06:12:18 GMT -05:00
https://www.coursehero.com/file/18657578/Half-lifeGizmo/
, 2. What remains at the end of the decay process? Daughter Atoms
3. Is the rate of decay fastest at the beginning, middle, or end of the process? The rate of
decay is fastest near the beginning.
Get the Gizmo ready:
Activity A: ● Click Reset ( ). Be sure that User chooses
half-life and Random decay are selected.
Decay curves ● Check that the Half-life is 20 seconds and the
Number of atoms is 128.
Question: How do we measure the rate of radioactive decay?
1. Observe: Select the BAR CHART on the right side of the Gizmo and click Play.
A. What happens to the numbers of radioactive and daughter atoms as the simulation
m
er as
proceeds? The number of radioactive atoms decreases until they reach zero
co
eH w
and the number of daughter atoms increases.
o.
rs e
B. Do the numbers of radioactive and daughter atoms change at the same rate
ou urc
throughout the simulation? Explain. No, the numbers of daughter atoms increase
o
steadily while towards the end of the reaction, the radioactive atoms take
aC s
vi y re
longer to disappear.
2. Experiment: Click Reset, and select the GRAPH tab. Run a simulation with the Half-life set
ed d
to 5 seconds, and then run another simulation with the Half-life set to 35 seconds. Sketch
ar stu
each resulting decay curve graph in the spaces below.
is
Th
sh
This study source was downloaded by 100000793680026 from CourseHero.com on 06-25-2021 06:12:18 GMT -05:00
https://www.coursehero.com/file/18657578/Half-lifeGizmo/
