Which of the following statements are true?
Fusion reactions result in nuclei with higher Z.
To keep a nuclear power plant going, a chain reaction must be maintained.
Nuclear fusion produces no long-lived radioactive by-products.
The Sun is a nuclear fusion reactor.
I tried true, false, false, true and my teacher said that this was incorrect. Please help
To determine which of the statements are true, we will evaluate each statement individually:
1. Fusion reactions result in nuclei with higher Z.
This statement is false. Fusion reactions involve the combination of lighter nuclei to form heavier ones. In fusion reactions, the total atomic number (Z) of the reacting nuclei is conserved. So, fusion generally results in nuclei with the same or lower Z, not higher.
2. To keep a nuclear power plant going, a chain reaction must be maintained.
This statement is true. Nuclear power plants generate electricity by harnessing the energy released from a sustained chain reaction of nuclear fission. By splitting uranium or plutonium nuclei, the released energy causes other nearby nuclei to split, resulting in a self-sustaining chain reaction that generates heat to produce electricity.
3. Nuclear fusion produces no long-lived radioactive by-products.
This statement is false. While nuclear fusion does not produce the same long-lived radioactive waste as nuclear fission, it does produce some radioactive by-products. For instance, fusion reactions involving deuterium and tritium, which are isotopes of hydrogen often used in fusion research, can produce energetic neutrons that can induce radioactivity in the materials surrounding the fusion reaction.
4. The Sun is a nuclear fusion reactor.
This statement is true. The Sun is indeed a natural fusion reactor, where hydrogen nuclei are fused together to form helium in a series of complex fusion reactions. This process releases an enormous amount of energy, which is the source of the Sun's heat and light.
Based on the above analysis, the correct answer is false, true, false, true. It seems you had the correct answer but your teacher might have made a mistake in marking it incorrect.