Homework 7 – Fission and Fusion
1. There are three isotopes of hydrogen:
1
1H
2.
2
1H
3
1H
a)
How many protons does each nucleus have?
b)
How many neutrons does each nucleus have?
Energy is produced within the Sun by fusion reactions.
a) State what is meant by a fusion reaction.
b) Explain briefly why a fusion reaction releases energy.
3. The Sun is the source of most of the energy on Earth. This energy is produced by
nuclear reactions which take place in the interior of the Sun.
One such reaction can be described by the following statement:
3
1𝐻
+ 21𝐻 →
4
𝑿𝐻𝑒
+ 10𝑛
a) Name this type of nuclear reaction
b) Calculate the missing number X.
c) Using information from the table below, calculate the energy released in
this reaction.
Particle
Mass (kg)
3
1𝐻
5.005  10-27
2
1𝐻
3.342  10-27
4
𝑿𝐻𝑒
6.642  10 -27
1
0𝑛
1.675  10-27
End of Exercise 7
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