1. What is an alpha particle? Write its symbol ,
including the atomic and mass numbers in the
correct positions.
An alpha particle is a helium
nucleus emitted by "some" radioactive
substances, originally regarded as a
'ray'.
2. What is a beta particle?Write
its symbol , including the atomic
and mass numbers in the correct
positions.
A beta particle is a fast-moving electron emitted by
radioactive decay of substances (originally regarded as
rays).
3. Give the names of four radioisotopes.
3H
Half life: 12.32
14C
Half life:5,730 × 103
50V
Half life:1.4 × 1017
87Rb
Half life:4.75 × 1010
4. What does it mean if a
substances is radioactive?
If a substance is 'radioactive' it means that the atoms inside the substance is not stable, the nuclei in these atoms can decay.
It changes one type of atom into another and releases radiation (the exact type of radiation depends on the substances). It has
a chance of causing mutations in organic cells.
5. How and where are radionuclides
produced?
Radionuclides are produced when an atom has an unstable
nucleus. They may occur naturally, but can also be artificially
produced.
6. Sketch a radioactive decay curve for a substance that starts with an activity of 1600 counts per minute
and has a half-life of 2 hours.
7. If a radioactive substance decays
from 400 counts per minute to 50
counts per minute in 9 hours, what is
its half-life?
8. Alpha radiation consists of particles
that can be easily stopped by our skin,
but they are still considered a potential
risk to our health. Explain why.
9. Consider the composition of alpha
and beta particles. When a beam of alpha
particles and a beam of beta particles are
fired into an electric field, they move in
opposite directions. Why do you think this
is?
10. Write a short paragraph describing how
the work of Marie Curie influenced future
work in different areas of science.
11. Describe why the Bohr model gives us much
more information than Dalton’s early model of the
atom.
12. Radiation produced from the decay of radioactive atoms can be very dangerous, but it can also be used
in life-saving medical treatments. Imagine you are a doctor wanting to reassure a patient about a treatment
based on exposure to radiation. List the main ideas that you would want to tell your patient.
-The treatment could potentially
be harmful in the long run.
-There may be certain risks
involved in this treatment.