Balancing Equations (pgs. 250-254) Chemical Equations & Reactions Balancing Equations (pgs. 250-254)

WARMUP Decide whether the following equations are “balanced” or not. Na + MgF2 2NaF + Mg Cu(NO3)2 + Na2CO3 CuCO3 + NaNO3 P4O10 (s) P4 (s) + 5O2 (g)

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

Helpful Tips Balance one element at a time. Update all atom counts after adding a coefficient. If an element appears more than once per side, balance it last. Balance polyatomic ions as single units. “1 SO4” instead of “1 S” and “4 O” Balance H atoms and O atoms after atoms of all other elements have been balanced.

Practice NH4NO3 + Ba3(PO4)2 Ba(NO3)2 + (NH4)3PO4

Practice Aluminum acetate and magnesium sulfate react to form aluminum sulfate and magnesium acetate.

Balancing Example 2 Al + CuCl2  Cu + AlCl3 3 3 2 Aluminum and copper(II) chloride react to form copper and aluminum chloride. 2 Al + CuCl2  Cu + AlCl3 Al Cu Cl 3 3 2 2  1 1 2 3  2  6 3  6   3

Avoid Most Common Mistakes writing incorrect chemical formulas for reactants or products trying to balance an equation by changing subscripts