Spring 2021, First Midterm
Please answer all questions. Show details of your calculations. Please do not give just final answers. Please use the
correct units.
By signing your name you attest that this is your individual personal work not copied from a third party.
Please edit, then return this Word docx document with your answers.
Name: Yuen Sun UIN: 672039114 UID: yuensun2
Question 1
a. In neutron cancer therapy, the following reaction can be used to destroy tumors with boron brought at
a cancer tumor’s site:
❑ 1 ❑ 10 ❑ 4
0 n + 5 B → 2 H e + ¿ 3Li7
b) Calculate the energy release from the fission reaction:
1 235 1 137 96
0n +92U 30n +53I +39Y
Use: m(92U235) = 235.0439 amu, m(0n1) = 1.00866497 amu, m(53I137) = 136.98355 amu, m(39Y96) = 95.801747 amu, 1
amu = 931.481 MeV.
Q = (1.00866497+235.0439-3*1.00866497-136.98355-95.801747) * 931.481 = 224.7412712Mev
c) Deuterium from sea water could be used in the future for producing fusion energy. Balance, then calculate the
energy release or the Q-values of the two branches of the DD fusion reaction:
2 2 1
1D + 1D ? + 1H
2 2 1
1D + 1D ? +0n
Use: m(1D2) = 2.014102 amu, m(1T3) = 3.016049 amu, m(2He3) = 3.0160293 amu , m(1H1) = 1.007825 amu, 1 amu =
931.481 MeV.
D2 + 1D2 1T3 + 1H1
1
Q = (2.014102*2-3.016049-1.007825)*931.481= 4.0333127Mev
D2 + 1D2 0n1 + 2He3
1
Q = (2.014102*2-1.00866497-3.0160293)*931.481= 3.269218Mev
Question 2
Write down the units and the abbreviations of the following radiological quantity:
Radiological Quantity Conventional System Unit SI System Unit
Activity Curie/gram Becquerel/gram
Using the law of radioactive decay calculate the fraction of the tritium isotope (N 0-N(t))/N0 decaying into the He3
isotope. The half-life of tritium is 12.33 years.
1. Within 1 year.
(1/2)1/12.33 = 0.9453346 fraction = (1-0.9453346)/1 = 0.0546654
This study source was downloaded by 100000899606070 from CourseHero.com on 02-22-2026 22:53:42 GMT -06:00
https://www.coursehero.com/file/85857147/NPRE-402-Spring-2021-First-Midterm-Yuen-Sundocx/