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Concentration of Solutions Chapter 13.3
Objectives Given the mass of solute and volume of solvent, calculate the concentration of a solution Given the concentration of a solution, determine the amount of solute in a given amount of solution Given the concentration of a solution, determine the amount of solution that contains a given amount of solute
Concentration Measure of the amount of solute in a given amount of  solvent or solution Solutions Dilute or concentrated Dilute – relatively small amount of solute in a solvent Concentrated – relatively large amount of solute in a solvent ,[object Object],[object Object]
Making a 0.500 M Solution of NaOH Step 1:   Determine mass needed M =  0.500 M  = mol solute =   mass of NaOH needed   =   0.500 mol NaOH  x mol solute L solution mol solute 1.00 L 0.500 M 1.00 L X =  0.500 mol NaOH 40.0 g NaOH 1 mol NaOH =  20.0 g NaOH ,[object Object],[object Object]
Practice Problems You have 3.50 L of solution that contains 90.0 g of sodium chloride, NaCl.  What is the molarity of that solution? You have 0.8 L of a 0.5 M HCl solution.  How many moles of HCl does this solution contain? To produce 40.0 g of silver chromate, you will need at least 23.4 g of potassium chromate in solution as a reactant.  All you have on hand in the stock room is 5 L of 6.0 M K2CrO4 solution.  What volume of the solution is needed to give you the 23.4 g K2CrO4 need for the reaction?
Molality Concentration of a solution expressed in moles of solute per kilogram of solvent. m  -  symbol Written as 1 m solution of NaOH One molal solution of sodium hydroxide 1 mol NaOH in 1 kg of solvent moles solute (mol) molality  =    mass of solvent (Kg)
Practice Problems A solution was prepared by dissolving 17.1 g of sucrose (table sugar, C12H22O11) in 125 g of water.  Find the molal concentration of this solution. A solution of iodine, I2, in carbon tetrachloride, CCl4, is used when iodine is needed for certain chemical tests.  How much iodine must be added to prepare a 0.489 m solution of iodine in CCl4 if 100.0 g of CCl4 is used?
Chapter 13.3 : Concentration of Solutions
Chapter 13.3 : Concentration of Solutions

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Chapter 13.3 : Concentration of Solutions

  • 2. Objectives Given the mass of solute and volume of solvent, calculate the concentration of a solution Given the concentration of a solution, determine the amount of solute in a given amount of solution Given the concentration of a solution, determine the amount of solution that contains a given amount of solute
  • 3.
  • 4.
  • 5. Practice Problems You have 3.50 L of solution that contains 90.0 g of sodium chloride, NaCl. What is the molarity of that solution? You have 0.8 L of a 0.5 M HCl solution. How many moles of HCl does this solution contain? To produce 40.0 g of silver chromate, you will need at least 23.4 g of potassium chromate in solution as a reactant. All you have on hand in the stock room is 5 L of 6.0 M K2CrO4 solution. What volume of the solution is needed to give you the 23.4 g K2CrO4 need for the reaction?
  • 6. Molality Concentration of a solution expressed in moles of solute per kilogram of solvent. m - symbol Written as 1 m solution of NaOH One molal solution of sodium hydroxide 1 mol NaOH in 1 kg of solvent moles solute (mol) molality = mass of solvent (Kg)
  • 7. Practice Problems A solution was prepared by dissolving 17.1 g of sucrose (table sugar, C12H22O11) in 125 g of water. Find the molal concentration of this solution. A solution of iodine, I2, in carbon tetrachloride, CCl4, is used when iodine is needed for certain chemical tests. How much iodine must be added to prepare a 0.489 m solution of iodine in CCl4 if 100.0 g of CCl4 is used?