Question 1

Which scientist first interpreted the results of uranium-235 neutron bombardment as the splitting of the nucleus into two smaller nuclei, leading to the naming of the process 'nuclear fission'?

Accepted Answer

Lise Meitner

Question 2

What is the primary force responsible for holding nucleons together in the nucleus at close distances?

Accepted Answer

Strong nuclear force

Question 3

In a typical induced uranium-235 fission reaction, what is the main form in which energy is released?

Accepted Answer

Kinetic energy of fission fragments

Question 4

Which equation explains the origin of the immense energy released during nuclear fission?

Accepted Answer

$$E = mc^2$

Question 5

A chain reaction in nuclear fission is best described as:

Accepted Answer

A process where the products of one reaction event stimulate further reaction events

Question 6

Why does fission not occur in the natural reserves of uranium found in uranium mines?

Accepted Answer

Most neutrons are absorbed by U-238, which is not fissile

Question 7

What is the critical mass in the context of nuclear fission?

Accepted Answer

The mass of fissile material above which chain reactions are self-sustaining

Question 8

Which material was used as a neutron moderator in the first nuclear reactors to slow down neutrons for fission?

Accepted Answer

Graphite

Question 9

What is the process of increasing the percentage of U-235 in uranium called?

Accepted Answer

Enrichment

Question 10

Which of the following is a major historical example of a nuclear reactor accident caused by loss of cooling after a natural disaster?

Accepted Answer

Fukushima (Japan, 2011)

Question 11

A breeder reactor breeds which fissile isotope from U-238?

Accepted Answer

Pu-239

Question 12

The mass defect in a nucleus is best described as:

Accepted Answer

The difference between the total mass of the nucleus and the sum of the masses of its individual nucleons

Question 13

Which of these nuclei has the greatest mass?

Accepted Answer

Uranium

Question 14

In which of these nuclei does the proton have the least mass?

Accepted Answer

Iron

Question 15

Which nuclear process is responsible for the creation of most elements heavier than iron in the universe?

Accepted Answer

Supernova nucleosynthesis

Question 16

In a fusion reaction that converts a pair of hydrogen isotopes to an alpha particle and a neutron, most of the energy released is in the form of:

Accepted Answer

Kinetic energy of the alpha particle

Question 17

For nuclear fission, is the mass of the resulting products less than, equal to, or more than the reactants? What about for fusion?

Accepted Answer

Less in fission; less in fusion

Question 18

Which of the following is NOT a component of a typical nuclear fission reactor?

Accepted Answer

Gamma ray shield

Question 19

Why is nuclear fusion more difficult to achieve on Earth than in stars?

Accepted Answer

The temperatures required to overcome electrical repulsion are extremely high

Question 20

Which of the following statements about fusion power is correct?

Accepted Answer

Fusion fuel (hydrogen) is plentiful and the chief byproduct is nonradioactive helium

Chapter 34: Nuclear Fission and Fusion – Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard