Page 231 - Chemistry eBook

Challenging Balancing Equations Example
Balance the following equation:
Ca(OH)2 + (NH4)2 SO4 CaSO4+ NH3 + H2O Make a chart.
Now let’s balance the equation to make both sides even.
a. Ca is even on both sides. Don’t touch any compound with Ca in it (unless you have no other choice.)
b. There are six Os on the left side and only five on the other. Therefore, we will add a coefficient of 2 in front of the entire H2O molecule:
Ca(OH)2 + (NH4)2 SO4 CaSO4+ NH3 + 2H2O
Element
LEFT SIDE:
Ca(OH)2 + (NH4)2 SO4
RIGHT SIDE: CaSO4+ NH3 + H2O
Ca
1
1
O
6 (O2+O4=O6)
5 (O4+O=O5)
H
10 (H2 +H8)
5 (H3+H2=H5)
N
2
1
S
1
1
UNIT 6: MATH IN CHEMISTRY © 230