Predicting Products of Chemical Equations by Reaction Type Answer Key (CHEM 1405)

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Predicting Products – Double Replacement Reactions

AB  +  CD      AD  +  CB

In double replacement reactions the cations of two compounds exchange places and form two new compounds.  Write complete BALANCED equations.

 

1. aluminum iodide      +      mercury (II) chloride      

2AlI₃     +     3HgCl₂         2AlCl₃     +     3HgI₂

 

2. silver nitrate      +      potassium phosphate      

3AgNO₃     +     K₃PO₄         Ag₃PO₄     +     3KNO₃

 

3. calcium acetate +      sodium carbonate      

Ca(C₂H₃O₂)₂     +     Na₂CO₃         2NaC₂H₃O₂     +     CaCO₃

 

4. ammonium chloride +      mercury (I) acetate      

2NH₄Cl     +     Hg₂(C₂H₃O₂)₂         Hg₂Cl₂     +     2NH₄C₂H₃O₂

 

5. ammonium chloride +      hydrochloric acid      

NH₄Cl     +     HCl         No reaction

 

6. calcium nitrate +     hydrochloric acid      

Ca(NO₃)₂     +     2HCl         CaCl₂     +     2HNO₃

 

7. iron (II) sulfide +      hydrochloric acid      

FeS     +     2HCl         H₂S     +     FeCl₂

 

8. copper (II) hydroxide +      acetic acid      

Cu(OH)₂     +     2HC₂H₃O₂         Cu(C₂H₃O₂)₂     +     2H₂O

 

 

 

Predicting Products – Single Replacement Reactions

A  +  BC      AC  + B

Step 1 – Write the formulas of the reactants on the left side of the yield sign

Step 2 – Look at the Activity Series table to determine if the replacement can happen

Step 3 – If the replacement can occur, complete the reaction and balance it. 

If the reaction cannot occur, write NR (no reaction) on the product side.  Write complete BALANCED equations.

 

1. lead      +      zinc acetate      

Pb     +     Zn(C₂H₃O₂)₂         No reaction

 

2. iron      +      aluminum oxide      

2Fe     +     Al₂O₃         Fe₂O₃     +     2Al

 

3. silver nitrate      +      nickel      

2AgNO₃     +     Ni         Ni(NO₃)₂     +     2Ag

 

4. sodium bromide      +      iodine      

2NaBr     +     I₂         No reaction

 

5. sodium      +      water      

2Na     +     2H₂O         2NaOH     +     H₂

 

6. sodium iodide      +      bromine      

2NaI     +     Br₂         2NaBr     +     I₂

 

7. calcium      +      hydrochloric acid      

Ca     +     2HCl         CaCl₂     +     H₂

 

8. silver      +      sulfuric acid (H₂SO₄)      

Ag     +     H₂SO₄         No reaction

 

 

Predicting Products – Combustion

C_xH_x   +   O₂     CO₂   +   H₂O

Hydrocarbons react with oxygen to form carbon dioxide and water.  Write complete BALANCED equations.

 

1. methane (CH₄) +      oxygen      

CH₄     +     O₂         CO₂     +     2H₂O

 

2. ethane (C₂H₆) +      oxygen      

2C₂H₆     +     7O₂         4CO₂     +     6H₂O

 

3. propane (C₃H₈) +      oxygen      

C₃H₈     +     5O₂         3CO₂     +     4H₂O

 

4. butane (C₄H₁₀) +      oxygen      

2C₄H₁₀     +     13O₂         8CO₂     +     10H₂O

 

5. pentane (C₅H₁₂) +      oxygen      

C₅H₁₂     +     8O₂         5CO₂     +     6H₂O

 

6. hexane (C₆H₁₄)      +      oxygen      

2C₆H₁₄     +     19O₂         12CO₂     +     14H₂O

 

7. The combustion of ethene (C₂H₄)

C₂H₄     +     3O₂         2CO₂     +     2H₂O

 

8. The combustion of benzene (C₆H₆)

2C₆H₆     +     15O₂         12CO₂     +     6H₂O

 

 

Predicting Products – Synthesis Reactions

A   +   B      AB

In synthesis reactions, two or more reactants combine to form one compound.  Write complete BALANCED equations.

 

1. calcium      +      oxygen      

2Ca     +     O₂         2CaO

 

2. copper      +      sulfur            copper (II) sulfide

Cu     +     S         CuS

 

3. calcium oxide      +      water            calcium hydroxide

CaO     +     H₂O         Ca(OH)₂

 

4. hydrogen       +      nitrogen      

3H₂     +     N₂         2NH₃

 

5. hydrogen      +     chlorine      

H₂     +     Cl₂         2HCl

 

6. silver      +      sulfur      

Ag     +     S         Ag₂S

 

7. aluminum      +      bromine      

2Al     +     3Br₂         2AlBr₃

 

8. sodium      +      iodine      

2Na     +     I₂         2NaI

 

 

Predicting Products – Decomposition Reactions

AB      A   +   B

Decomposition reactions break down into the elements that make up the reactant or into smaller compounds.  For the reactions below, assume each reactant breaks up into its component elements.  Write complete BALANCED equations.

 

1. NaCl            2Na     +     Cl₂

 

 

2. MgBr₂             Mg     +     Br₂

 

 

3. CaCl₂             Ca     +     Cl₂

 

 

4. KI             2K     +     I₂

 

 

5. AlCl₃             2Al     +     3Cl₂

 

 

6. Ag₃N             6Ag     +     N₂

 

 

7. CuCl₂             Cu     +     Cl₂

 

 

8. MnCl₂             Mn     +     Cl₂