Environmental Engineering Reference
In-Depth Information
Problem 6.1
(a) Calculate the mass deficit (
m
) in atomic mass units (amu) of the following fission reaction.
(Use literature values for the exact masses of the isotopes and neutrons.)
235
U
139
Xe
95
Sr
+
n
→
+
+
2n
(b) Calculate the energy (MeV) released per one fission. (c) Calculate the energy released per
kilogram of
235
U, and compare it to the energy released in the combustion of 1 kg of carbon.
Problem 6.2
(a) Calculate the mass deficit (
m
) in atomic mass units (amu) of the following fusion reaction.
2
D
3
T
4
He
+
→
+
n
(b) Calculate the energy released (MeV) per one fusion. (c) Calculate the energy released per
kilogram of deuterium.
Problem 6.3
In a nuclear accident there is a release of
90
Sr that emits
γ
rays with a half-life of 28.1 y. Suppose
1
g was absorbed by a newly born child. How much would remain in the person's body after 18
and 70 years if none is lost metabolically?
µ
Problem 6.4
The isotope
223
Ra has a half-life of 11.4 days.
223
Ra decays at a rate of 1 Ci per gram of radium
isotope. (Ci
3.7E(10) disintegrations/sec.) What will be the decay rate (Ci) of the 1-gram
sample after 10, 100, and 1000 days?
=
Curie
=
Problem 6.5
The isotope
129
I has a half-life of 15.7 years. In a nuclear power plant accident, 1 kg of the iodine
isotope is dispersed into the surroundings of the plant. How much of the iodine isotope will remain
in the surroundings after 1, 10, and 100 years?
Problem 6.6
Define the following terms and give examples as appropriate:
fissile nucleus
fertile nucleus
chain reaction
