Chemistry
Nuclear Chemistry
Name______________________________
Nuclear Equations
Directions: Complete the following nuclear equations and list the type of decay (alpha,
α, beta, β, or
gamma, γ) to the right of the equation.
Type of Decay
1.
214 Po
84
 210
82 Pb + _______
____________
2.
222 Rn
86
 _______ + 24 He
____________
3.
230 Th
90

____________
4.
214 Pb
82
 _______ +
0
-1e
____________
5.
226 Ra
88
 _______ + 42 He
____________
6.
239 Np
93
 _______ +
____________
7.
_______ 
8.
234 U
92

9.
206 Pb
82
+ 42 He
 _______
____________
10.
254 Pa
91
 _______ + -10e
____________
11.
226 Ra
88
12. 214
82 Pb
226 Ra
88
+ ________
234
90Th
234 Np
93
0β
-1
+ 42 He
____________
 _______
 _______ +
4 He
2
 _______ + -10 e + 00 γ
____________
+ gamma rays
__________
____________
Nuclear Equations II
Directions: Complete the nuclear equations by filling in the blank space.
13. 238
92 U

14. 234
90Th
 ______ + -10 e
15. 234
91Pa
 ______ +
16. 234 U
 ______ +
92
17.
234
90Th

230
90Th
226
88 Ra
+ _______
0
-1e
4 He
2
+ ______
18. 226
88 Ra

19. 222
86 Rn
 ______ + 42 α
222 Rn
86
+ ______
20.
______ 
21.
214
82 Pb
 ______ +
22.
214
83 Bi

214
84 Po
+ ______
23.
214
84 Po

210
82 Pb
+ ______
24.
210
82 Pb
25.
210
83 Bi
214
82 Pb
 ______ +

26. 210
84 Po
210
84 Po
+ 24 He
0
-1β
0
-1e
+ _______
 _______ + 42 α
27. This series of nuclear reactions is called a ___________________ _______________
______________.
28. It shows radioactive Uranium – 238 will form non-radioactive _____________. This
process takes approximately _________________________years.
29. Fill in the blank with the isotopic symbol that will complete and balance the following
nuclear equations:
a. 21 H  21 H 
 11 H  ______
b.
63
29
c.
241
95
Cu

1
1


Am
d. ______ 
e.
64
30
f.
235
92
Zn
U


H
237
93
2
1

0
1

1
0
e
n
H
1
0

n
25
13
 _______
Al
Np  _______






3
2
He

1
0
n
_______
138
56
Ba
 301 n
 _______
30. Write balanced nuclear equations for the following:
a. The alpha decay of neptunium-237
b. The beta decay of bismuth-210
c. The neutron bombardment of tin-120
d. The electron capture of iodine-128
e. The nuclear transmutation of mercury-201 that consists of two alpha decays and 1
beta decay.
f. The electron capture of antimony-123 followed by the emission of 2 neutrons.
g. Alpha-particle bombardment of plutonium-239 produces a neutron and another
isotope. Write the nuclear equation for this reaction and identify the isotope.
h. When bombarded with a neutron, lithium-6 produces an alpha particle and an
isotope of hydrogen. Write the nuclear equation for this reaction. What isotope
of hydrogen is produced?
i. With what particle would you bombard sulfur-32 with to produce hydrogen-1 and
phosphorus-32? Write the appropriate nuclear equation.
j. With what particle would you bombard bismuth-209 to produce astatine-211 and
2 neutrons? Express this reaction in the form of a nuclear equation.
31. Write an equation to describe the alpha decay of a radium-226 nucleus to form a radon
nucleus.
32. Write an equation to describe the alpha decay of a radon nucleus to form a polonium-218
nucleus.
33. Write an equation to describe the beta decay of a lead-214 nucleus to form a bismuth-214
nucleus.
34. Write an equation to describe the alpha decay of a uranium-238 nucleus to form a
thorium nucleus.
35. Write an equation to describe the beta decay of a thorium-234 nucleus to form a
protactimium nucleus.
36. Write the series of equations involving three alpha decays and two beta decays that show
the transmutation of a uranium-238 nucleus into a radium-226 nucleus.
Isotopic Notation & Nuclear Reactions
37. How many protons and neutrons do each of the following have?
a)
241
95 Am
b)
63
29 Cu
c)
3
__ H
d)
40
__ Ar
38. The following are elements with mass numbers. Rewrite the numbers in isotopic
notation.
a) gold-197
b) magnesium-25
c) lead-210
d) iodine-131
39. Complete the nuclear equation for the alpha emission (decay) for the following isotopes:
a)
219
86 Rn

c)
234
92 U

b)
227
89 Ac

d)
253
100 Fm

40. Complete the nuclear equation for the beta emission (decay) for the following isotopes:
a)
42
19 K

c)
14
6C

b)
131
53 I

d)
253
98 Cf

41. Complete the following nuclear equations and identify them as either alpha (α) or beta (β)
decay.
a) 31H
 23 He + ______
b) 218
84 Po

214
82 Pb
+ ______
c) 211
83 Bi
35S
d) 16


207
81Tl
35
17 Cl
+ ______
+ ______
42. Fill in the blanks in the following radioactive decay series:
224 Ra
88
 42 He + ______  42 He + ______  ______ +
212
82 Pb

0
-1e
+ ______
Changes in the Nucleus
43. Nuclear reactions change the composition of an atom’s _____________________.
44. The attractive force that overcomes the electric repulsion between protons is the
______________ _________________ force.
45. Almost all the atoms you encounter have _________________ nuclei.
46. All nuclei with atomic numbers greater than 83 are __________________________.
47. Alpha, beta and gamma radiation are distinguished by their charge, _________________,
and penetrating power.
48. When an atom emits alpha, beta or gamma radiation, it is undergoing
_________________ decay.
Answer each of the following in the space provided:
49. Why do nuclei need neutrons to be stable?
________________________________________________________________________
___________________________________________________
50. In any radioactive decay, the sum of the mass numbers and atomic numbers must be
___________ before and after the reaction.
a) greater
b) the same
c) less
d) unpredictable
51. The most dangerous form of radiation to the human body is
a) beta radiationb) gamma radiation c) alpha radiation d) They are equally dangerous
52. To be stable, atoms with more than 20 protons need increasingly more
a) neutrons than protons
b) electrons than protons
c) electrons than neutrons
d) protons than neutrons
53. The sun produces energy by means of
a) gamma radiation b) beta decay
222
56. 226
88 Ra  86 Rn + ______
57.
14
6C
27 Al
58. __

14
7N
+
4
__ He
c) alpha decay
d) nuclear fusion
+ ______

12 C
6
+ ______
Write a nuclear equation for the following reactions:
59. alpha decay of polonium-210
_______________________________________________________
60. beta decay of tritium ( 31H )
_________________________________________________________
61. alpha decay of thorium-230
________________________________________________________
62. alpha decay of
231
91 Pa
_____________________________________________________________
63. What particle bombards Beryllium-9 if it forms carbon-12 and neutrons?
_________________________________________________________________________
64. beta decay of
165
61 Pm
_____________________________________________________________
65. What isotope is bombarded with alpha particles to produce oxygen-17 and hydrogen-1?
________________________________________________________________________
66. alpha decay of
146
62 Sm
____________________________________________________________
67. beta decay of 198
85 At
_____________________________________________________________
68. bombardment of boron-10 with neutrons to produce Li-7 and another particle
_______________________________________________________________
69. beta decay of
152
54 Xe
________________________________________________________________
Nuclear Bombardment Problems
70. Bombardment of aluminum-27 by alpha particles produces phosphorus-30 and one other
particle. Write the nuclear equation for this reaction and identify the other particle.
71. When bombarded with neutrons, cobalt-59 is converted to cobalt-60. What is the nuclear
equation for this reaction?
72. Neutron bombardment of plutonium-239 yields americium-240 and another particle.
Write the nuclear equation and identify the other particle produced.
73. Alpha-particle bombardment of plutonium-239 produces a neutron and another isotope.
Write the nuclear equation for this reaction and identify the isotope.
74. When bombarded with neutrons, lithium-6 produces an alpha particle and an isotope of
hydrogen. Write the nuclear equation for this reaction. What isotope of hydrogen is
produced?
75. With what particle would you bombard sulfur-32 to produce hydrogen-1 and phosphorus32? Write the appropriate nuclear equation.
76. With what particle would you bombard bismuth-209 to produce astatine-211 and 2
neutrons? Express this reaction in the form of a nuclear equation.
2
77. 1
H  ________  24 He
  147 N  _______  11H
4
78. 2
½ Life Notes
Definition: The time it takes for _________________ of the atoms in a
______________________
material to _______________. This time can range from _________sec to
__________________ of years.
Examples:
79. Carbon-14,
remain?
½ life = 5730 years. If you start with 128g, how long until 8g
TIME
AMOUNT
80. If the ½ life of element x is 100. years, how much of the isotope will remain after 500
years if you start with 128g?
TIME
AMOUNT
81. 20.g of a radioisotope with a ½ life of 200 hours is prepared in a nuclear reactor.
How much will remain after 600. hours?
TIME
AMOUNT
Half-life Problems
82. The half-life of cesium-137 is 30.2 years. If the initial mass of a sample of cesium-137 is
1.00 kg, how much will remain after 151 years.
83. With a half-life of 28.8 years, how long will it take for 1.00g of strontium-90 to decay to
0.125g?
84. A 1.000-kg block of phosphorus-32, which has a half-life of 14.3 days, is stored for 100.1
days. At the end of this period, how much phosphorus-32 remaining
85. There are 3.29 g of iodine remaining in a sample originally containing 26.3 g of iodine126. The half-life of iodine-126 is 13 days. How old is the sample?
86. A sample of air from a basement is collected to test for the presence of radon-222, which
has a half-life of 3.8 days. However, delays prevent the sample from being tested until
7.6 days have passed. Measurements indicate the presence of 6.5 g of radon-222. How
much radon-222 was present in the sample when it was initially collected?
87. The half-life of carbon-14 is 5730 years. If a sample originally contained 3.36 g of C-14,
how much is present after 22,920 years?
88. Gold-191 has a half-life of 12.4 hours. After one day and 13.2 hours, 10.6 g of gold-191
remains in a sample. How much gold-191 was originally present in the sample?