Types of Chemical Reactions Glencoe Chapter 23

Types of Reactions  5 basic types of chemical reactions 1. Combustion – burning of a reactant in the presence of O 2  Releases energy in the form of heat and light  Forms an oxide of the reactant  Sometimes combustion is incomplete and other products are formed along with the ashes left behind CH 4 (g) + O 2 (g) → CO 2 (g) +2H 2 O (g) +energy

Types of Reactions  5 basic types of chemical reactions 2. Synthesis – 2 or more reactants combine to form a larger and more complex compound Product is larger or more complex than any of the reactants 6CO 2 (g)+ 6H 2 O(l) → C 6 H 12 O 6 (aq)+ 6O 2 (g) 2Na (s) + Cl 2 (g) → 2NaCl(aq)

Types of Reactions  5 basic types of chemical reactions 3. Decomposition – reaction where a complex compound is broken down to produce 2 or more simpler substances 2NaHCO 3 (s) → Na 2 CO 3 (s)+ H 2 O(g)+ CO 2 (g) 2H 2 O(l) → 2H 2 (g) + O 2 (g)

Types of Reactions  5 basic types of chemical reactions 4. Single Displacement – reaction in which one element replaces another in a compound Zn(s) + 2HCl(aq) → ZnCl 2 (aq) + H 2 (g)

Types of Reactions  5 basic types of chemical reactions 5. Double Displacement – reaction in which two elements in different compounds exchange positions 2KI(aq) + Pb(NO 3 ) 2 (aq) → PbI 2 (s) + 2KNO 3 (aq)