Practice Suppose that a solution containing 3.50 grams of Na3PO4 is mixed with a solution containing 6.40 grams of Ba(NO3)2. Na3PO4 + Ba(NO3)2  Ba3(PO4)2 + NaNO3 What is the limiting reactant and what is the excess reactant How many grams of Ba3(PO4)2 can be formed? How much of the excess reactant remains

Solution Dilution Stock solutions – solutions stored in concentrated forms HCl is stored as 12M stock solution When diluting acids, always add concentrated acid to water

Dilution Equation M1V1 =M2V2 Mol1=Mol2 The number of moles of a solute doesn’t change when we dilute a solution

Problems To what volume (in ML) should you dilute 100 ML of a 5M CaCl2 Solution to obtain 0.750M CaCl2 solution ? What volume of a 6M NaNO3 should you use to make 0.525L of a 1.20M NaNO3 solution?

Solution Stoichiometry We can use the volume and concentration of a reactant or product to calculate its amount in moles The conceptual plan is Volume A Amount A( in moles ) Amount B in moles Volume B Volume B

What mass in grams of CO2 forms? Practice What volume in ML of a 0.150M HNO3 solution will completely react with 35.7ml of a 0.108M Na2CO3 solution according to the following reaction?  Na2CO3(aq) + 2HNO3(aq) ---> 2NaNO3(aq) + H2O(l) + CO2(g) What mass in grams of CO2 forms?

Aqueous solutions and solubility How do solids such as salt and sugar dissolve in water?

Electrolyte and non electrolyte solutions Salt solution conducts electricity while sugar solution doesn’t Salt – Ionic compound Sugar – Molecular compound Ionic compounds completely dissociate in to ions in a solution and act as charge carriers and they are strong electrolytes Molecular compounds dissolve in water as intact molecules

Solubility of Ionic compounds A compound is said to be soluble - If it completely dissolves in water A compound is insoluble - If its not completely dissolved in water Solid AgNO3 in water is completely soluble and makes a strong electrolyte Solid AgCl in water is insoluble and remains as a solid in water

Strong Electrolytes and Nonelectrolytes Strong electrolytes: Substances that dissolves in water to form solutions that conducts electricity Example: NaCl Nonelectrolytes: substances that do not dissociate in to ions when dissolved in water are called nonelectrolytes Example: All molecular compounds except acids

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