Reaction Nuclear reactions

Like physical changes and chemical reactions, nuclear reactions are accompanied hy energy changes. Nuclear reactions, however, produce significantly more energy than physical and chemical processes. In nuclear reactions, a significant amount of the mass of the reactants is actually converted into energy. 

The atom is composed of many types of subatomic particles, but only three types will be important in this course. Protons and neutrons exist in the atom s nucleus, and electrons exist outside the nucleus. The nucleus (plural, nuclei) is incredibly small, with a radius about one ten-thousandth of the radius of the atom itself. (If the atom were the size of a car, the nucleus would be about the size of the period at the end of this sentence.) The nucleus does not change during any ordinary chemical reaction. (Nuclear reactions are described in Chapter 21.) The protons, neutrons, and electrons have the properties listed in Table 3.1. These properties are independent of the atom of which the subatomic particles are a part. Thus, the atom is the smallest unit that has the characteristic composition of an element, and in that sense, it is the smallest particle of an element. 

Like chemical reactions, nuclear reactions must be balanced with respect to both charge and mass. 

The radioactive decay processes you have just read about are all examples of nuclear reactions. Nuclear reactions are expressed by balanced nuclear equations just as chemical reactions are expressed by balanced chemical equations. However, in balanced chemical equations, numbers and types of atoms are conserved in balanced nuclear equations, mass numbers and charges are conserved. 

Most chemical reactions are focused on the outer electrons of an element, sharing, swapping, and bumping electrons into and out of the combining partners of a reaction. Nuclear reactions are different. They take place within the nucleus. 

Like chemical reactions, nuclear reactions may occur in several steps. For example, the first reaction here is actually an overall process that occurs in three steps ... 

There are two kinds of chemical reactions so-called ordinary chemical reactions and nuclear reactions. In ordinary chemical reactions there are no changes to the nuclei of the atoms. The only interaction between the atoms is among the atoms electrons. In nuclear reactions the electrons do not matter. What matters are changes that take place in the atoms nuclei. This chapter is about ordinary chemical reactions nuclear reactions are discussed in Chapters 13 and 14. 

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