Types of Chemical Equations
For the reaction between each of the following substances, first draw an ion box and
find the products of these double replacement reactions. Then, write a balanced
chemical equation, showing all species present as well as their states. Use your data
booklet on page 4 to find out which species is aqueous or insoluble. Finally, write a
balanced net ionic equation. A net ionic equation shows only the reacting species in a
chemical reaction, and does not include spectator ions. Assume that all reactions take
place in water and that all reacting substances are ionic.
1. Sodium hydroxide and iron (III) chloride
Ion Box
Cation
Anion
Products
Na+
OH-
NaCl (aq)
Fe3+
Cl-
Fe(OH)3(s)
Balanced chemical equation:
3NaOH(aq) + FeCl3(aq) 3NaCl(aq) + Fe(OH)3(s)
Complete ionic equation: Aqueous solutions break into anions and cations
3Na+(aq) + 3OH-(aq) + Fe3+(aq) + 3Cl-(aq) 3Na+(aq) +3Cl-(aq) + Fe(OH)3(s)
Net Ionic equation: Remove spectator ions
3OH-(aq) + Fe3+(aq) Fe(OH)3(s)
Spectator ions: Na+, Cl-
2. Potassium sulphide and copper (II) nitrate
Ion Box
Cation
Anion
Products
K+
S 2-
KNO3(aq)
Cu2+
NO3-
CuS(s)
Balanced chemical equation:
K2S(aq) + Cu(NO3)2(aq) 2KNO3(aq) + CuS(s)
Complete ionic equation:
2K+(aq) + S2-(aq) + Cu2+(aq) + 2NO3-(aq) 2K+(aq) + 2NO3-(aq) + CuS(s)
Net ionic equation:
S2-(aq) + Cu2+(aq) CuS(s)
Spectator ions: K+, NO3-
