NUCLEAR EQUATIONS
(c) distinguish between nucleon number (mass number) and proton number (atomic number)
(d) show an understanding that an element can exist in various isotopic forms, each with a different number of neutrons
(e) use the usual notation for the representation of nuclides
(f) appreciate that nucleon number, proton number, and mass-energy are all conserved in nuclear processes
(g) represent simple nuclear reactions by nuclear equations
(h) show an appreciation of the spontaneous and random nature of nuclear decay
(i) show an understanding of the nature and properties of α-, β- and γ- radiations (β+ is not included: β- radiation will be
taken to refer to β–)
(j) infer the random nature of radioactive decay from the fluctuations in count rate
DECAY PROCESSES
Radioactive decay processes
 decay
Z
N
Z–2
N–2
proton number Z

2 fewer protons
2 fewer neutrons
– decay
–
Z
N
Z+ 1
N–1

proton number Z
1 more proton
1 less neutron
+ decay
+
Z–1
N+1

Z
N
proton number Z
1 less proton
1 more neutron
decay
Z
N
proton number Z

same protons
and neutrons
NUCLIDE NOTATION
A periodic table may be needed
A
1 Write down the nuclear notation ( Z X ) for:
(a)
an alpha particle
(b)
a proton
(c)
a hydrogen nucleus
(d)
a neutron
(e)
a beta particle
(f)
a positron.
A
2 Write down the nuclear notation ( Z X ) for
(a)
carbon 13
(b)
nitrogen 14
(c)
neon 22
(d)
tin 118
(e)
iron 54
PRACTISE WITH NUCLEAR EQUATIONS
1
The isotope
element?
235
U decays into another element, emitting an alpha particle. What is the
This element decays, and the next, and so on until a stable element is reached. The
complete list of particles emitted in this chain is:
235
92 U  [, , , , , , , , , , ]  X.
What is the stable element X? (You could write down each element in the series, but
there is a quicker way.)
2
The following fission reaction can take place in a nuclear reactor:
235
1
137
95
1
92 U  0 n 55 Cs  [ ] Rb  0 n.
Complete the equation, showing how many neutrons are produced in the reaction. What
is the significance of the number of neutrons produced?
Why are the products of the reaction, caesium-137 and rubidium-95, likely to be
radioactive? What type of decay are these isotopes likely to show?
3
Boron absorbs neutrons with results as follows:
10
5
B  01 n  73 Li  24  .
Why is boron suitable for use in a control rod?
4
27
When the isotope 13 Al is irradiated with alpha particles, the products from each
aluminium nucleus are a neutron, and a nuclide that emits positrons to give the stable
30
isotope 14 Si . Write nuclear equations for these two processes.
5
Complete the following nuclear equations. In each case describe the decay process:
131
53 I

Xe 
67
0
31Ga  1e
11
6C

Zn
B  01e

99m
43Tc
6

0
1e
Tc   .
The Manhattan Project, the development of the atomic bomb, led to the discovery of the
transuranic elements (elements beyond uranium in the periodic table). Plutonium,
element 94, is formed by the bombardment of uranium-238 with neutrons. The nuclear
equations are:
238
1
239
92 U 0 n 92 U
239
239
0
92 U 93 Np  1 e
239
239
0
93 Np  94 Pu 1 e
Complete the following nuclear equation for the formation of americium:
239
94 Pu
201 n  Am 
0
1e.
Curium is produced if plutonium-239 is bombarded with alpha particles. If the curium
242
isotope is 96 Cm , complete the equation
239
94 Pu

4
2

If curium is made the target for alpha particle bombardment californium is produced.
Complete the nuclear equation to find the atomic number of californium:
242
96 Cm

4
245
Cf
2 
 01n.
By firing heavier particles such as carbon or boron ions at the target materials heavier
elements can be synthesised. Complete the nuclear equation (Lw is lawrencium)
252
Cf 
9
5B
 Lw  4 01 n.
One of the transuranic elements is commonly found in the home. Which is this and where
is it used?
NUCLEAR EQUATIONS
Activity
Describe the structure
of an atom
Define nuclide, isotope
and nucleon
Know what A, Z and N
are and use them
correctly
Write nuclear equations
for Alpha emissions
Write nuclear equations
for Beta emissions
Know the properties of
alpha, beta and gamma
radiation
Completed
and
understood
Further action
Checked