How to find the product of chemical reaction
There is no easy way you can find the products of a chemical reaction without doing experiment.
But you can predict them
The first step---identifying the type of reaction involved---is usually the most difficult. The primary reaction types students encounter are displacement, acid-base and combustion. They are easily identified if the tell-tale signs are known. Displacement reactions involve two ionic compounds with cations and anions, such as sodium sulfate, in which sodium (Na+) is the cation and sulfate (SO2-?) is the anion. Ionic compounds always consist of a metal and a nonmetal or polyatomic (multiple-atom) anion. Decomposition reactions involve a single compound breaking into two or more compounds. Acid-base reactions must involve an acid (identified by its chemical formula that begins with “H,” such as HCl). Combustion reactions involve hydrogen or a hydrocarbon (such as CH4) reacting with oxygen (O2). Displacement Reactions Identify the cation and anion of the compounds involved in the reaction, as well as their charges. Sodium chloride (NaCl), for example, consists of a sodium ion (Na+) and a chloride ion (Cl-).
Exchange the anions of the two reactants to determine the products of the reaction. Displacement reactions take this general form:
AB + CD = AD + CB
Thus, for a reaction between sodium chloride (NaCl) and silver nitrate (AgNO2):
NaCl + AgNO2 ? NaNO2 + AgCl
Determine whether the products are soluble.In the example from Step 2, NaNO2 is soluble and thus remains in solution, but AgCl is insoluble and will form a precipitate.
Verify that the reaction is balanced by adding coefficients in front of the reactants and products as necessary to ensure that each type of atom is present on each side of the reaction arrow in equal numbers. In the example from Step 2, the left side of the equation contains 1 Na, 1 Cl, 1 Ag, 1 N, and 3 O; the right side contains 1 Na, 1 Cl, 1 Ag, 1 N, and 3 O. Thus, the reaction is balanced.
Acid-Base Reactions Identify the acidic compound (containing H+ in its formula) and the basic compound (usually a hydroxide, OH-).
Determine the products according to the general reaction:
acid + base = salt + water
For example, the reaction of hydrochloric acid (HCl) with sodium hydroxide (NaOH) produces sodium chloride and water:
HCl + NaOH = NaCl + H2O
Determine if the salt is soluble or insoluble by referring to the solubility rules.
Balance the reaction. In this case, the reaction from Step 2 is already balanced.
But you can predict them
The first step---identifying the type of reaction involved---is usually the most difficult. The primary reaction types students encounter are displacement, acid-base and combustion. They are easily identified if the tell-tale signs are known. Displacement reactions involve two ionic compounds with cations and anions, such as sodium sulfate, in which sodium (Na+) is the cation and sulfate (SO2-?) is the anion. Ionic compounds always consist of a metal and a nonmetal or polyatomic (multiple-atom) anion. Decomposition reactions involve a single compound breaking into two or more compounds. Acid-base reactions must involve an acid (identified by its chemical formula that begins with “H,” such as HCl). Combustion reactions involve hydrogen or a hydrocarbon (such as CH4) reacting with oxygen (O2). Displacement Reactions
Identify the cation and anion of the compounds involved in the reaction, as well as their charges. Sodium chloride (NaCl), for example, consists of a sodium ion (Na+) and a chloride ion (Cl-).
Exchange the anions of the two reactants to determine the products of the reaction. Displacement reactions take this general form:
AB + CD = AD + CB
Thus, for a reaction between sodium chloride (NaCl) and silver nitrate (AgNO2):
NaCl + AgNO2 ? NaNO2 + AgCl
Determine whether the products are soluble.In the example from Step 2, NaNO2 is soluble and thus remains in solution, but AgCl is insoluble and will form a precipitate.
Verify that the reaction is balanced by adding coefficients in front of the reactants and products as necessary to ensure that each type of atom is present on each side of the reaction arrow in equal numbers. In the example from Step 2, the left side of the equation contains 1 Na, 1 Cl, 1 Ag, 1 N, and 3 O; the right side contains 1 Na, 1 Cl, 1 Ag, 1 N, and 3 O. Thus, the reaction is balanced.
Acid-Base ReactionsIdentify the acidic compound (containing H+ in its formula) and the basic compound (usually a hydroxide, OH-).
Determine the products according to the general reaction:
acid + base = salt + water
For example, the reaction of hydrochloric acid (HCl) with sodium hydroxide (NaOH) produces sodium chloride and water:
HCl + NaOH = NaCl + H2O
Determine if the salt is soluble or insoluble by referring to the solubility rules.
Balance the reaction. In this case, the reaction from Step 2 is already balanced.
