Chemistry 1441 1st Edition Lecture 11 Outline of Last Lecture I Percent Composition of Compounds II Empirical and Molecular formulas III Combustion Analysis Outline of Current Lecture I Molarity and Solution Stoichiometry II Electrolytes III Precipitation Reactions Current Lecture I Molarity and Solution Stoichiometry Molarity M Molarity relates moles of solute to volume of the solution It is a quantitative amount and can be calculated by moles of solute volume of solution Example 0 38 g of NaNO3 is placed in a 50 0mL flask The flask is then filled with water to the mark on the neck What is the molarity of the resulting solution 0 38 g NaNO3 1 mol NaNO3 85g NaNO3 4 47 10 3 mol NaNO3 85 g is the molar mass of NaNO3 50 0mL 050L 4 47 10 3 050 0 090M NaNO3 II Electrolytes Strong Electrolytes HCl HNO3 HClO4 H2SO4 NaOH Weak Electrolytes CH3COOH HF HNO2 NH3 H2O Nonelectrolytes NH2 2CO CH3OH C2H5OH C6H12O6 C12H22O11 Strong Acids HClO4 H2SO4 HI HBr HCl HNO3 Strong Bases LiOH NaOH KOH Ca OH 2 Sr OH 2 Ba OH 2 Hydrogen ions H are yielded when the acid is dissolved in water this means that H will be on the right side of a chemical equation Hydroxide ions OH are yielded when the acid is dissolved in water this means that OH will be on the right side of a chemical equation III Precipitation Reactions Precipitation reactions involve an insoluble product Solids that do not dissolve in water are called insoluble Example Pb NO3 2 aq 2KI aq PbI2 s 2KNO3 aq