Lorraine Pettigrew             George Washington High School
                               3535 East 114th Street
                               Chicago, IL 60617
To learn to balance simple equations by the trial and error method.

MATERIALS: 1 inch paper squares

STRATEGIES: Divide an 8 1/2" x 11" piece of paper into 1" squares. Label with symbols as shown below: You should end up with the following numbers of squares: 8 - Mg, Na 20 - O 16 - H 8 - N, P, S, C Another set of strips should be cut in sets of double squares and lettered as below. Use 6 O2 6 H2 Balance the equations using the squares you made to represent the atoms in the equations below. Make the number of each atom on the left equal to the number of the same atoms on the right. Calculations Insert the coefficients on the lines 1. ___ Mg + ___O2 = ___MgO

2. ___H2O + ___N2O3 = ___HNO3 3. ___Na + ___H2O = ___NaOH + ___H2 4. ___P2O5 + ___H2O = ___H3PO4 5. ___CS2 + ___O2 = ___CO2 + ___SO2

For a web based lesson go to
and print out the worksheet. (Answers for the worksheet are at
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