# Introduction to Equations

1. Using a concept map, define and relate the following terms:
a.)        chemical equation
b.)        reactants
c.)        products
d.)
à
e.)        coefficients

2.      Determine a three step process for balancing equations.
1.
2.
3.

3.      How are equations balanced?

4.      What is the importance of subscripts in an equation?  What is a general rule for subscripts when balancing equations?

5.      Use the following equation to answer questions a – f:
2 Na  +  2 H2O
à   2 NaOH  +  H2

a.)    How many sodium atoms are on both sides of the equation?
b.)    How many hydrogen atoms are on both sides of the equation?
c.)    How many oxygen atoms are on both sides of the equation?
d.)    Why is hydrogen written as H2 instead of H?
e.)    To what other elements does d.) apply?

6.      Use the following equation to answer questions a – d:
3 Ca(OH)2  +  2 H3PO4
à   Ca3(PO4)2  +  6 H(OH)

a.)    How many calcium atoms are on both sides of the equation?
b.)    How many phosphate ions are on both sides of the equation?
c.)    How many hydrogen atoms and how many oxygen atoms are
on both sides of the equation?
d.)  What is another way to write H(OH)?

7.      Balance the following equations:
a.)  _____ Al  +  _____ N2
à   _____ AlN
b.)  _____ NaCl  +  _____ H2SO4
à   _____ Na2SO4  +  _____HCl
c.)  _____ Al  +  _____ CuSO4
à   _____ Al2(SO4)3  +  _____ Cu
d.)  _____ P  +  _____ O2
à   _____ P2O5
e.)  _____ Fe(OH)3
à   _____ Fe2O3  +  _____ H2O
f.)  _____ Na  +  _____ H2O
à   _____ NaOH  +  _____ H2
g.)  _____ H2  +  _____ S
à   _____ H2S
h.)  _____ FeCl3  +  _____ Ca(OH)2
à   _____ Fe(OH)3  +  _____ CaCl2
i.)  _____ C  +  _____ O2
à   _____ CO
j.)  _____ KNO3
à   _____ KNO2  +  _____ O2