Reaction bombardment

More than 1500 radioactive isotopes have been prepared in the laboratory. The number of such isotopes per element ranges from 1 (hydrogen and boron) to 34 (indium). They are all prepared by bombardment reactions in which a stable nucleus is converted to one... 

Radioactivity The ability possessed by some natural and synthetic isotopes to undergo nuclear transformation to other isotopes, 513 applications, 516-518 biological effects, 528-529 bombardment reactions, 514-516 diagnostic uses, 516t discovery of, 517 modes of decay, 513-514 nuclear stability and, 29-30 rate of decay, 518-520,531q Radium, 521-522 Radon, 528 Ramsay, William, 190 Random polymer 613-614 Randomness factor, 452-453 Raoult s law A relation between the vapor pressure (P) of a component of a solution and that of the pure component (P°) at the same temperature P — XP°, where X is the mole fraction, 268... 

Decay Reactions. The Kinetics of Decay Reactions. Bombardment Reactions and the Growth of Radioactivity. 

The number of naturally occurring radionuclides is limited and few are of analytical value. For the majority of purposes artificial radionuclides are manufactured. Bombardment reactions are generally used in their production. A suitable target material is exposed to an intense flux of the appropriate particles in a nuclear reactor or particle accelerator such as a cyclotron. Thermal neutrons in the reactor... 

The growth and decay of a nuclide in the target during a bombardment reaction may be exemplified by a generalized sequence... 

Nuclear bombardment reactions in which the product is radioactive constitute the basis of radioactivation analysis (p. 456). Although in principle any bombardment-decay sequence may be used the analyst is largely concerned with thermal neutron activation. Equation (10.13) relates the induced activity to the amount of the parent nucleide (analyte). However, practical difficulties arise because of flux inhomogeneities. It is common therefore to irradiate a standard with very similar characteristics alongside the sample, e.g. for a silicate rock sample a standard solution would be evaporated on to a similar amount of pure silica. On the assumption that identical specific activities for the analyte are then induced in the sample and standard, the amount w2 of analyte is readily calculated from... 

Bombardment reactions are often summarized in a terse form, such as Be(a,n). This means that the target (9Be) is bombarded by a particles ( He), and that neutrons (in) are produced. By the rules for balancing nuclear equations, we know that j=C also is produced. Give the complete balanced nuclear equation for each of the following transmutation bombardments (p stands for proton, and d stands for deuteron in this notation). 

Bombardment reactions often are summarized in a terse form, as explained in Problem 3 Give the complete balanced nuclear equation for each of the following transmutation bombardments... 

Other nuclear transmutations can lead to the synthesis of entirely new elements never before seen on Earth. In fact, all the transuranium elements—those elements with atomic numbers greater than 92—have been produced by bombardment reactions. Plutonium, for example, can be made by bombarding uranium-238 with a particles ... 

As was the case for the previously discovered transuranium elements, element 97 was first produced via a nuclear bombardment reaction. In December, 1949, ion-exchange separation of the products... 

Neutrons bear no charge, so they are not repelled by nuclei as positively charged projectiles are. They do not need to be accelerated to produce bombardment reactions. Neutron beams can be generated in several ways. A frequently used method involves bombardment of beryllium-9 with alpha particles. 

What are nuclear bombardment reactions Explain the shorthand notation used to describe bombardment reactions. 

Fill in the missing symbols in the foUowLng nuclear bombardment reactions. 

The Periodic Table has been extended from U (Z = 92) to currently Z = 112 since 1940 by synthetic methods. Some synthetic elements have extremely long half-lives (e.g. 24896Cm, ty2 3.5 x 105 yr), others moderate half-lives (e.g. 24997Bk, ty2 300 d) or short half-lives (e.g. 261io4Rf, 0/2 65 s). Their syntheses have involved fusion and bombardment reactions, for example ... 

The uranium-239 then undergoes two beta decays, first to Np, and then to Pu, which is a fissionable material and the desired product. Write balanced nuclear equations for the bombardment reaction and the two beta-decay reactions. 

The bombardment of nuclei with small high-energy particles causes the bombarded nuclei to (1) change into stable nuclei, (2) change into radioactive nuclei, (3) break into smaller pieces (fission), or (4) form larger nuclei (fusion). Most bombarding particles are accelerated by using cyclic or linear accelerators. Bombardment reactions have been used to produce elements that are not found in nature. 

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