Unit 4 Test Review

Which of the following BEST describes what occurs in a fusion reaction?

• Two low mass nuclei are joined to form one nucleus and gives off energy.

• A single nucleus divides into two or more nuclei and gives off energy.

• Electrons are shared between the nuclei.

• A chemical reaction occurs between the nuclei.

Nuclear reactors convert heat energy into mechanical energy, used to generate electrical energy, by

• turning a turbine with steam.

• harnessing electromagnetic discharge.

• gathering solar radiation.

• using an electron transfer system.

The high energy yields created by nuclear fission are due to

• binding nuclei.

• chain reactions.

• hydrogen bonding.

• secondary recovery.

How many half-lives does it take a radioactive substance to decay until only one-eighth of the original substance remains?

• Two

• Three

• Six

• Eight

The half-life for a 100-gram sample of radioactive element X is 5 days. How much of element X remains after 10 days have passed?

• 25 g

• 50 g

• 75 g

• 100 g

The graph shows the radioactive decay of a bone that is found to contain 1/8 of the carbon-14 found in living animals today.

Approximately how old is the bone?

• 5,730 years

• 11,460 years

• 17,190 years

• 22,920 years

Where does the energy released in a nuclear decay reaction come from?

• electrons

• chemical bonds

• positrons

• the binding energy of the nucleus

What occurs in a nuclear power plant when Uranium-235 splits into two smaller isotopes?

• nuclear fusion

• nuclear fission

• a chemical reaction

• a neutralization reaction

The graph shows the electricity production costs for different energy sources in the United States over time. 

Which statement is best supported by the graph?

• Nuclear and coal have similar production costs,and petroleum's production costs have increased over time.

• Nuclear and coal have similar production costs, and petroleum's production costs have decreased over time.

• Nuclear and petroleum have similar production costs, and gas's production costs have increased over time.

• Nuclear and petroleum have similar production costs, and gas's production costs have stayed the same over time.

Which of the following describes a relationship between an atomic property and nuclear power generation?

• Atoms such as the uranium-235 isotope absorb energy when they are split into smaller atoms.

• Atoms such as the uranium-235 isotope can bond with other atoms to form larger molecules, releasing energy in the process.

• Atoms such as the uranium-235 isotope can bond with other atoms to form larger molecules, absorbing energy in the process.

• Atoms such as the uranium-235 isotope release energy when they are split into smaller atoms.