Topic 7.2

A graph of the variation of average binding energy per nucleon with nucleon number has a maximum. What is indicated by the region around the maximum?

• The position below which radioactive decay cannot occur

• The region in which fission is most likely to occur

• The position where the most stable nuclides are found

• The region in which fusion is most likely to occur

The average binding energy per nucleon of the  $_8^{15}O$  nucleus is 7.5 MeV. What is the total energy required to separate the nucleons of one nucleus of O-8?

• 53 MeV

• 60 MeV

• 113 MeV

• 173 MeV

In a nuclear fission reaction, nucleus X splits into nucleus Y and nucleus Z. Which of the following gives a possible order of the nuclei from lowest to highest binding energy per nucleon?

• Z → Y → X

• Z → X → Y

• Y → X → Z

• X → Z → Y

The rest mass of a proton is 938 MeV  $c^{-2}$ . The energy of a proton at rest is

• 9.38 J

•  $9.38\ \times10^{8\ }\times\left(3\ \times10^8\right)^{2\ }J$  

•  $9.38\ \times10^{8\ }eV$  

•  $9.38\ \times10^{8\ }\times\left(3\times10^8\right)^{2\ }eV$  

Data concerning nuclides are plotted using the axes below.

What are the axis labels for this graph?

• y - axis: Binding energy per nucleon; x-axis: number of nucleons

• y - axis: Binding energy; x-axis: number of protons

• x - axis: Binding energy per nucleon; y-axis: number of protons

• x - axis: Binding energy; y-axis: number of nucleons

The nuclear reaction

 $H_1^2+H_1^3\ ->\ He_2^4+n_0^1$  

is an example of

• nuclear fission

• radioactive decay

• nuclear fusion

• artificial transmutation

The mass defect for deuterium is $4\times10^{-30\ }kg$  

What is the binding energy of deuterium?

•  $4\times10^{-7\ }eV$  

•  $8\times10^{-2\ }eV$  

•  $2\times10^{-6\ }eV$  

•  $2\times10^{12\ }eV$