GIZMOS STUDENT EXPLORATION: HALF-LIFE
Student Exploration: Half-life
Vocabulary: daughter atom, decay, Geiger counter, half-life, isotope, neutron,
radiation, radioactive, radiometric rating, radioactive waves
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 microwave? When popcorn is in the microwave, popping noise
comes out opf the microwave.
2. If you turn the microwave on for two minutes, is the rate of popping always the
same, or does it change? Explain. The rate is different because the radioactive
waves pops the popcorn at
different times.
Gizmo Warm-up
Like an unpopped kernel in the microwave, a
radioactive atom can change at any time.
Radioactive atoms change by emitting radiation in
the form of tiny particles and/or 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 the decay of a radioactive substance. Be
sure the sound is turned on and click Play (
).
1. What do you see and hear? I hear popping noises and I see radioactive waves.
Note: The clicking sound you hear comes from a Geiger counter, an instrument
that detects the particles and energy emitted by decaying radioactive atoms.
2. What remains at the end of the decay process? Daughter atoms replaced the
radioactive atoms. So there is only daughter atoms.
, 3. Is the rate of decay fastest at the beginning, middle, or end of the process?
Beginning of the process is where the rater of decay is the fastest.
Student Exploration: Half-life
Vocabulary: daughter atom, decay, Geiger counter, half-life, isotope, neutron,
radiation, radioactive, radiometric rating, radioactive waves
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 microwave? When popcorn is in the microwave, popping noise
comes out opf the microwave.
2. If you turn the microwave on for two minutes, is the rate of popping always the
same, or does it change? Explain. The rate is different because the radioactive
waves pops the popcorn at
different times.
Gizmo Warm-up
Like an unpopped kernel in the microwave, a
radioactive atom can change at any time.
Radioactive atoms change by emitting radiation in
the form of tiny particles and/or 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 the decay of a radioactive substance. Be
sure the sound is turned on and click Play (
).
1. What do you see and hear? I hear popping noises and I see radioactive waves.
Note: The clicking sound you hear comes from a Geiger counter, an instrument
that detects the particles and energy emitted by decaying radioactive atoms.
2. What remains at the end of the decay process? Daughter atoms replaced the
radioactive atoms. So there is only daughter atoms.
, 3. Is the rate of decay fastest at the beginning, middle, or end of the process?
Beginning of the process is where the rater of decay is the fastest.
