s.levey+teaching+reaction+wiki.

five chemical reactions.
there are five different chemical reactions in chemistry. these five reactions are: //synthesis, decomposition, single displacement, double displacement,// and //combustion//. **synthesis** is the reaction where two or more substances are combined to produce a single, more complex substance. **decomposition** is where a single substance is broken down into two or more simpler substances (so, pretty much the opposite of synthesis.) **single displacement** is when a free atom becomes an ion and an ion becomes a free element. this may sound a little confusing, but basically, elements switch around on either side of an equation. **double displacement** is where a reaction in which the positive ion of one compound replaces the positive ion of the other compound to produce two new compounds. **combustion** is when a substance rapidly combines with oxygen to produce one or more oxides.

reaction one: synthesis. reaction two: decomposition. reaction three: single displacement. reaction four: double displacement. reaction five: combustion.