HOMEWORK 3.4 – NUCLEAR RADIATION
1. A student made some statements about particles found in atoms.
A.
B.
C.
D.
E.
Relative mass is almost zero
Charge = 1+
Charge = 0
Found inside the nucleus
Relative mass = 1
Identify the two statements which apply to both a proton and a neutron.
(1 mark)
2. Some smoke detectors make use of radiation which is very easily stopped by tiny smoke particles moving
between the radioactive source and the detector.
The most suitable type of radioisotope for a smoke detector would be:
A. An alpha emitter with a long half – life
B. A gamma emitter with a short half – life
C. An alpha emitter with a short half – life
D. A gamma emitter with a long half – life
(1 mark)
3. Which particle will be formed when an atom of 211 83 Bi loses an α – particle and the decay product then loses a
β – particle?
A
210
7𝐴𝑢
B
209
80𝐻𝑔
C
208
81𝑇𝑙
D
207
82𝑃𝑏
(1 mark)
4. The following represents part of a natural radioactive decay series.
α
β
x
U
→
y
Th
→
231
Pa
Which of the following represents the mass numbers x and y?
A
B
C
D
X
Y
239
232
237
235
235
231
233
231
(1 mark)
5. There are three different types of neon atom.
TYPE OF ATOM
NUMBER OF PROTONS
NUMBER OF NEUTRONS
NUMBER OF ELECTRONS
a) Copy and complete the table to show the numbers of protons, neutrons and electrons in each neon atom.
(1 mark)
b) What term is used to describe these different types of neon atoms?
(1 mark)
6. The diagram represents the structure of an atom.
a) Fill in the missing information for (i) and (ii)
(1 mark)
b) The element uranium has unstable atoms. These atoms give out radiation and a new element is formed.
c) State the number of protons and neutrons for the particle 23490Th.
(1 mark)
d) Radon is another element which gives out radiation.
Write the nucleic notation for element X.
(1 mark)
7. Na-24 is a radioactive isotope of sodium with a half-life of 15 hours. A sample of Na-24 has a mass of 200g.
a) What is meant by half-life?
b) What will be the mass of the sample after 120 hours?
(2 marks)
8. a) Phosphorus-32 and strontium-89 are two radioisotopes used to study how far mosquitoes travel.
Strontium-89 decays by emission of a beta particle. Complete the nuclear equation for the decay of strontium89.
89
Sr →
(1 mark)
b) A mosquito fed on a solution containing phosphorus-32 is released. Phosphorus-32 has a half-life of 14 days.
When the mosquito is recaptured 28 days later, what fraction of the phosphorus-32 will remain?
(1 mark)
9. Name the three types of radiation emitted from radioisotopes.
(1 mark)
10. If a radioisotope undergoes the following series of emissions what would be the overall change in the
nucleus?
     
11. Thorium-227 decays by alpha emission.
a) Complete the nuclear equation for the alpha decay of thorium-227.
(1 mark)
(1 mark)
227
Th →
b) A sample of thorium-227 was placed in a wooden box. A radiation detector was held 10 cm away from the box.
Why was alpha radiation not detected?
(1 mark)
12. Give two examples of applications of radioisotopes.
(2 marks)
13. What is the name of the apparatus used to measure radiation?
(1 mark)
TOTAL = 20 MARKS