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Net Ionic Equations. HW: Net Ionic equations worksheet. Net Ionic Equations. Most ionic compounds dissociate completely into cations and anions when they dissolve in water. Written for double and single replacement reactions. Net Ionic Equations.
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Net Ionic Equations • HW: Net Ionic equations worksheet
Net Ionic Equations • Most ionic compounds dissociate completely into cations and anions when they dissolve in water. • Written for double and single replacement reactions
Net Ionic Equations • Write the complete ionic equation (includes all dissolved ionic compounds as their free ions.) Cl2 (g) + 2NaBr (aq) → Br2(l) + 2NaCl (aq)
Complete Ionic Equations (step 1) Cl2 (g) + 2NaBr (aq) → Br2(l) + 2NaCl (aq) Cl2(g) + 2Na+(aq) + 2Br-(aq)→ Br2(l) + 2Na+(aq) + 2Cl-(aq)
Spectator ions (step 2) • Spectator ion: not directly involved in a reaction. Appears on both sides of the equation. • In the previous problem, 2Na+(aq) is the spectator ion.
Net ionic equation (step 3) • Indicates only the particles that actually take part in the reaction. Cl2(g) + 2Br-(aq)→ Br2(l) + 2Cl-(aq) • Make sure that the charges balance on both sides of the equation
Net Ionic Equation (Example) • Solutions of Lead(II) acetate and cupric sulfate are mixed. • Write the balanced equation • Write the complete ionic equation • Identify the spectator ions • Write the net ionic equation
Balanced Equation Pb(C2H3O2)2(aq) + CuSO4(aq) → PbSO4(s) + Cu(C2H3O2)2(aq)
Complete Ionic Equation Pb2+(aq) + 2C2H3O2-(aq) + Cu2+(aq) + SO42-(aq)→ PbSO4(s) + Cu2+(aq) + 2 C2H3O2-(aq) Note: PbSO4 does not dissolve in water!
Identify Spectator Ions • 2C2H3O2-(aq) • Cu2+(aq) Appear on both sides of the equation
Net Ionic equation • Eliminate spectator ions Pb2+(aq) + SO42-(aq) → PbSO4(s) Note: zero net charge on reactant side; zero net charge on product side