Loading in 2 Seconds...
Loading in 2 Seconds...
Lesson Objective Calculate the concentration of solutions in units of molarity Calculate the dilution of solutions in units of molarity. Solutions are made in various concentrations Concentration depends on the amount of solute dissolved in a given amount of solvent
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
Lesson Objective • Calculate the concentration of solutions in units of molarity • Calculate the dilution of solutions in units of molarity
Solutions are made in various concentrations • Concentration depends on the amount of solute dissolved in a given amount of solvent • Molarity (M) – number of moles of solute dissolved in one liter of the solution • Units of mol/L or M Ex) 2 mol/L = 2 M • The higher the molarity, the more concentrated the solution • Molarity By Leridant[CC-BY-SA-2.5] Decreasing Concentration
Convert given units, if necessary, before plugging into the molarity equation • Mass to moles • Volume to liters Ex) 2 M solution of NaOHdescribes a solution in which every liter of solution contains 2 moles of NaOH • Calculating Molarity
Molarity Calculation • Write unknown and givens V = 500. mL m= 102 g Molar mass = 58.44 g/mol M = ? • Identify the formula and rearrange, if needed Ex) What is the concentration of a 500. mL salt solution containing 102 g of NaCl? (Molar mass of NaCl = 58.44 g/mol) • Convert units and find intermediates, if needed • Plug in and solve • Make sure the answer is reasonable
What is the molarity of an aqueous solution containing 40.0 g of glucose (C6H12O6) in 1.5L of solution? • Molarity Calculation
How many grams of NaOH are present in a 2.5 M solution? • Molarity Calculation
Dilution – process of decreasing the concentration of a solution by adding additional solvent • Number of solute particles does not change, but the amount of solvent is increased • Adding solvent increases the overall volume of the solution and decreases the concentration • Inversely proportional relationship between concentration and volume of solvent in a solution • Dilution
Use the following equation when performing dilution calculations • V1= volume of the original (stock) solution • M1 = molarity of the original (stock) solution • V2 = volume of the diluted solution • M2 = molarity of the diluted solution • Dilution Formula
Dilution Calculation • Write unknown and givens M1 = 2.0 M V1 = 1.5 L V2 = 4.0 L M2 = ? • Identify the formula and rearrange, if needed Ex) A 2.0 M solution of acid is diluted by increasing its volume from 1.5 L to 4.0 L. Calculate the molarity of the new solution. • Convert units and find intermediates, if needed • Plug in and solve 5. Make sure the answer is reasonable
What volume of a 3.00M KI stock solution would you use to make 0.300 L of a 1.25M KI solution? • Dilution Calculation
How many moles of solute are contained in 25 mL of 1.5MCa(OH)2?