Nonmetal single displacement

Displacing One Element by Another Activity Series As we said, displacement reactions have the same number of reactants as products. We mentioned doubledisplacement (metathesis) reactions in discussing precipitation and acid-base reactions. The other type, single-displacement reactions, are all oxidation-reduction processes. They occur when one atom displaces the ion of a different atom from solution. When the reaction involves metals, the atom reduces the ion when it involves nonmetals (specifically halogens), the atom oxidizes the ion. Chemists rank various elements into activity series—one for metals and one for halogens— in order of their ability to displace one another. 

To predict which single substitution reactions will occur, we need to know a little about the relative reactivities of some of the important metals and nonmetals. Some metals and a few nonmetals are listed in Table 8.2 in order of decreasing reactivity. A more complete list is given in Section 17.2. Hydrogen is included in the list of metals because it can be displaced from aqueous acids by reactive metals (Figure 8.5) and can displace less active metals from their compounds ... 

In this displacement reaction, a single element reacts with a compound and displaces another element from the compound. The products are a different element and a different compound than the reactants are. In general, a metal may displace another metal (or hydrogen), while a non-metal may displace only another nonmetal. 

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