The document discusses balancing chemical equations in 5 steps: 1) write the unbalanced equation, 2) count atoms on each side, 3) add coefficients to make atom numbers equal, 4) reduce coefficients to the lowest ratio, and 5) double check atom balance. It provides tips such as balancing one element at a time and updating all atom counts after each coefficient addition. An example reaction of aluminum and copper(II) chloride is given and balanced according to the steps.

1. Chemical Reactions
Balancing Equations
I II III IV V

2. A. Balancing Steps
1. Write the unbalanced equation.
2. Count atoms on each side.
3. Add coefficients to make #s equal.
Coefficient × subscript = # of atoms
4. Reduce coefficients to lowest
possible ratio, if necessary.
5. Double check atom balance!!!

3. B. Helpful Tips
s Balance one element at a time.
s Update ALL atom counts after adding
a coefficient.
s If an element appears more than
once per side, balance it last.
s Balance polyatomic ions as single
units.
• “1 SO4” instead of “1 S” and “4 O”

4. C. Balancing Example
Aluminum and copper(II) chloride react
to form copper and aluminum chloride.
2 Al + 3 CuCl2 → 3 Cu + 2 AlCl3
⁄
21 Al ⁄
1 2
⁄
31 Cu ⁄
1 3
⁄
62 Cl ⁄
3 6