Balancing Equations Test Questions

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Chemical reactions have the same number of atoms before the reaction as after the reaction. Balancing chemical equations is a basic skill in chemistry and testing yourself helps retain important information. This collection of ten chemistry test questions deals with balancing chemical reactions.

Question 1

Balance the following equation:

__ SnO2 + __ H2 → __ Sn + __ H2O

Question 2

Balance the following equation:

__ KOH + __ H3PO4 → __ K3PO4 + __ H2O

Question 3

Balance the following equation:

__ KNO3 + __ H2CO3 → __ K2CO3 + __ HNO3

Question 4

Balance the following equation:

__ Na3PO4 + __ HCl → __ NaCl + __ H3PO4

Question 5

Balance the following equation:

__ TiCl4 + __ H2O → __ TiO2 + __ HCl

Question 6

Balance the following equation:

__ C2H6O + __ O2 → __ CO2 + __ H2O

Question 7

Balance the following equation:

__ Fe + __ HC2H3O2 → __ Fe(C2H3O2)3 + __ H2

Question 8

Balance the following equation:

__ NH3 + __ O2 → __ NO + __ H2O

Question 9

Balance the following equation:

__ B2Br6 + __ HNO3 → __ B(NO3)3 + __ HBr

Question 10

Balance the following equation:

__ NH4OH + __ Kal(SO4)2·12H2O → __ Al(OH)3 + __ (NH4)2SO4 + __ KOH + __ H2O

Answers

1. 1 SnO2 + 2 H2 → 1 Sn + 2 H2O
2. 3 KOH + 1 H3PO4 → 1 K3PO4 + 3 H2O
3. 2 KNO3 + 1 H2CO3 → 1 K2CO3 + 2 HNO3
4. 1 Na3PO4 + 3 HCl → 3 NaCl + 1 H3PO4
5. 1 TiCl4 + 2 H2O + 1 TiO2 + 4 HCl
6. 1 C2H6O + 3 O2 → 2 CO2 + 3 H2O
7. 2 Fe + 6 HC2H3O2 → 2 Fe(C2H3O2)3 + 3 H2
8. 4 NH3 + 5 O2 → 4 NO + 6 H2O
9. 1 B2Br6 + 6 HNO3 → 2 B(NO3)3 + 6 HBr
10. 4 NH4OH + 1 Kal(SO4)2·12H2O → 1 Al(OH)3 + 2 (NH4)2SO4 + 1 KOH + 12 H2O

Tips for Balancing Equations

When balancing equations, remember chemical reactions must satisfy conservation of mass. Check your work to make certain you have the same number and type of atoms on the reactants side as on the products side. A coefficient (number in front of a chemical) is multiplied by all the atoms in that chemical. A subscript (lower number) is only multiplied by the number of atoms it immediately follows. If there is no coefficient or subscript, that is the same as a number "1" (which is not written in chemical formulas).