Mass-energy relationship in nuclear reactions

Virtually infinite amounts of energy are possible from fusion. Uranium supplies for fission power are limited, but heavy hydrogen, or deuterium (the most likely fusion fuel), is abundant. It is estimated that the deuterium in a cubic mile of seawater used as fusion fuel could provide more energy than the petroleum reserves of the entire world. 

From an environmental viewpoint, fusion power is much cleaner than fission power because fusion reactions (in contrast to uranium and plutonium fission reactions) do not produce large amounts of long-lived and dangerously radioactive isotopes. 

Flemnants of a supernova show temperatures of about 10 million degrees Celsius created when the star exploded. 

Calculate the mass defect and the nuclear binding energy for an a particle (helium nucleus). 

PLAN First calculate the sum of the individual parts of an a particle 

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Skill 7.1a-Understand how mass-energy relationships in nuclear reactions and radioactive decay requires the relationship E=mc2... 

Mass-Energy Relationship in Nuclear Reactions Transuranium Elements... 

SECTION 21.6 The energy produced in nuclear reactions is accompanied by measurable changes of mass in accordance with Einstein s relationship, A = Am. The difference in mass between nuclei and... 

Section 21.6 The energy produced in nuclear reactions is accompanied by measurable tosses of mass in accordance wilh Einstein s relationship, AE = c Am. The difference in mass between nuclei and the nucleons of which Ihey are composed is known as Ihe mass defect. The mass defect of a nuclide makes it possible to calculate its nuclear binding energy, Ihe energy required to separate Ihe nucleus into individual nucleons. Energy is produced when heavy nuclei split (fission) and when light nuclei fuse (fusion). 

The energy change AE that results from a mass change in a nuclear reaction (Am) is given by the Einstein mass-energy relationship AE = c Am. 

The mass-energy relationship can be used to predict the energy release in nuclear decay reactions, as illustrated in Example 17.3. 

The word mass refers to quantity of matter. It is closely related to the more familiar term weight. Section 3.4 explains the difference between mass and weight. The relationship shown in the equation tells us that matter is an extremely concentrated form of energy Conversions between matter and energy occur primarily in nuclear reactions. 

Notice that the products of the nuclear reaction have less mass than the reactants. The missing mass is converted to energy. In Chapter 1, we learned that matter is conserved in chemical reactions. In nuclear reactions matter can be converted to energy. The relationship between the amount of matter that is lost and the amount of energy formed is given by Einstein s famous equation relating the two quantities ... 

With nuclear reactions, the energies involved are so great that the changes in mass become easily measurable. One no longer can assume that mass and energy are conserved separately, but must take into account their interconversion via Einstein s relationship, E = me2. 

Reactions between an atomic nucleus and another particle are called nuclear reactions. In some such reactions, new nuclei are formed nuclear transmutations) in others the original nucleus is excited to a higher energy state (inelastic scattering) in a third class, the nucleus is unchanged (elasticscattering). Spontaneous nuclear transformations, which are involved in the radioactive decay of unstable nuclei, have be discussed in Chapter 4. In this chapter the enqrhasis is on the mass and energy relationships when a projectile interacts with a nucleus. 

These conversion factors are used in Example 25-5, together with the principle that the total mass-energy of the products of a nuclear reaction is equal to the total mass-energy of the reactants. The masses required in calculations based on nuclear reactions are nuclear masses. The relationship of a nuclear mass to a nuclidic (atomic) mass is... 

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