Chemical Reactions Predicting Products and Balancing Equations

I. Synthesis (Composition) Reactions A) Liquid hydrogen plus liquid oxygen yields gaseous water plus a lot of energy. A) Liquid hydrogen plus liquid oxygen yields gaseous water plus a lot of energy. H 2(l) + O 2(l) --> H 2 O (g) H 2(l) + O 2(l) --> H 2 O (g) reactants yield products reactants yield products 2H 2(l) + O 2(l) --> 2H 2 O (g) 2H 2(l) + O 2(l) --> 2H 2 O (g) Coefficients are used to balance equations. Coefficients are used to balance equations.

B. All these type reactions take the general form A + B --> AB A + B --> AB Two or more elements Two or more elements yielding a single yielding a single compound. compound. C. Fe (s) + O 2 (g) --> FeO 2 (s) Iron plus oxygen yields iron IV oxide (rust). Iron plus oxygen yields iron IV oxide (rust).

II. Decomposition Reactions All take the general form All take the general form A B ---> A + B A B ---> A + B 2KClO 3(s) -->2KCl (s) + O 2(g This reaction was one of the first reactions used to make pure oxygen. This reaction was one of the first reactions used to make pure oxygen. Salt producing ions in water is another example. 2NaCl (s) -->2Na (aq) + Cl 2(aq)

III. Single Replacement Reactions A. These take the form of A + BC -> AC + B Zn (s) + 2HCl (aq) ---> Zn (s) + 2HCl (aq) ---> ZnCl 2S) + H 2(g) ZnCl 2S) + H 2(g) This is one of the reactions we used in the lab to make hydrogen. This is one of the reactions we used in the lab to make hydrogen. B. They may also take the form C + AD --> AC + D F 2(g) + 2 KI (s) ----> 2KF (s) + I 2(g) 2KF (s) + I 2(g)

IV. Double Replacement Reactions Take the general form Take the general form AB + CD --> AD + CB HCl (aq) + NaOH (aq) --> acid base acid base NaCl (s) + HOH (l) NaCl (s) + HOH (l) salt water salt water Neutralization rxn (also how soap is made)

V. Combustion Reaction Take the general form of C x H y + O 2 --> CO 2 + H 2 O (excess) (excess) C x H y + O 2 --> CO + H 2 O (limited) (limited) Any hydrocarbon when burned produces carbon dioxide and water (gasoline and natural (gasoline and natural gas are other examples) gas are other examples)