Warm-Up A 55ml sample of a 0.102M potassium sulfate solution is mixed with 35ml of a 0.114M lead(II) acetate solution and this precipitation reaction occurs K2SO4(aq) +Pb(C2H3O2)2(aq) 2KC2H3O2(aq)+PbSO4(s) The solid PbSO4 found to have a mass of 1.01g .Determine the limiting reactant, the theoretical yield and percent yield?

Strong acids and weak Acids Strong acids dissociate completely in water Example: HCl Weak Acids: They do not completely dissociate in water Example : acetic acid Strong acids are strong electrolytes and weak acids are weak electrolytes

Solubility Rules for Ionic compounds in Water

Predict the solubility NiS Mg3(PO4)2 Li2CO3 NH4Cl

Precipitation Reactions Hard water – contains dissolved ions such as Ca2+ and Mg2+ which diminishes the effectiveness of soap Most laundry detergents contains substances such as sodium carbonate to remove these ions Na2CO3 (aq) --> 2Na+(aq)+ CO3 2- (aq)

Hardness of water The carbonate ions react with Ca2+ and Mg2+ ions to form precipitate which prevent their reaction with soap Ca2+(aq) + CO32-  → CaCO3(s) + 2Na+(aq) Mg2+(aq) + CO32-  → MgCO3(s) + 2Na+(aq) These reactions are called precipitation reactions

Precipitation reactions Pb(NO3)2(aq)+ 2KI(aq) = 2KNO3(aq) + PbI2(s) (Soluble) (soluble) (soluble) (insoluble) KI+NaCl No reaction happens Only insoluble compounds form precipitate

How to represent Aqueous Reactions Aqueous reaction can be represented by molecular, net ionic and complete ionic equations Molecular Equation – represents all the molecules Pb(NO3)2(aq)+ 2KI(aq) = 2KNO3(aq) + PbI2(s)

Complete ionic Equation Equations list all of the ions present as either reactants or products present in a reaction are complete ionic equation Pb2+(aq) +2NO3-(aq) +2K+(aq)+2I-(aq) PbI2(s)+2K+(aq)+ 2NO3-(aq) Strong electrolytes are always represented as their component ions in ionic equation

Spectator Ions Some of the ions in the equation remains unchanged on both sides of the equation. They are called spectator ions They do not participate in the reaction

Net Ionic equation Equation that shows only the species that actually change during the reaction are called net ionic equation

Write the molecular equation, complete ionic equation and net ionic equation for the following reaction HCl(aq) + KOH(aq) = KCl(aq) + H2O(l)