1. Examples
How many moles and milIimoles of benzoic acid (122.1 g/mol) are contained in 2.00 g of the pure acid?
How many grams of Na+ (22.99 g/mol) are contained in 25.0 g of Na2S04 (142.0 g/mol)?
Calculate the molar concentration of ethanol in an aqueous solution that contains 2.30 g of C2H5OH (46.07 g/mol) in 3.50 L of solution.
What mass of AgN0 3 (169.9 g/mol) is needed to convert 2.33 g of Na2CO3 (106.0 g/mol) to Ag2C03 ? (b) What mass of Ag2C03 (275.7 g/mol) will be formed?

2. Examples
A solution was prepared by dissolving 5.76 g of KCI.MgCI2.6H2O ( g/mol) in sufficient water to give L. Calculate
(a) the molar analytical concentration of KCl.MgCl 2 in this solution.
(b) the molar concentration of Mg2+.
(c) the molar concentration of Cl-.
(d) the weight/volume percentage of KCl.MgCl2 .6H20.
(e) the number of millimoles of Cl- in 25.0 mL of this solution.
(f) ppm K+.
(g) pMg for the solution.
(h) pCI for the solution.

3. Examples
What volume of M AgNO3 would be required to precipitate all of the I- in mL of a solution that contained ppt KI?
Exactly g of pure Na2C03 was dissolved in mL of M HCl.
(a) What mass in grams of CO2 were evolved?
(b) What was the molarity of the excess reactant (HCI or Na2C03)?