1 / 40

SOLUTIONS I

Goals

crescent
Download Presentation

SOLUTIONS I

An Image/Link below is provided (as is) to download presentation 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. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

    1. SOLUTIONS I Concentrations of solutions Chapter 11.1-11.4 McM Chapter 13.5 Silberberg

    2. Goals & Objectives See the following Learning Objectives on pages 543-544. Understand these Concepts: 13.14 Master these Skills: 13.3-4.

    3. Concentrations of Solutions Solution a homogeneous mixture, consisting of a Solute the dissolved species usually present to the lesser extent and a Solvent the dissolving species usually present to the greater extent

    4. A Sodium Chloride Solution Sodium chloride is the solute water is the solvent (understood)

    6. Concentration A measure of the amount of solute dissolved per given amount of solvent or solution. Typical units Percent by mass (% w/w) Molarity (M, mol/L) Molality (m) Proof

    7. Proof Approximately twice the percent by volume of alcohol Proof %Alcohol by Volume 26 13% 80 40% 190 95%

    8. Percent by Mass of Solute %mass of solute = g solute x 100 g solution A 25.9% solution of glucose contains: 35.0g of glucose /35.g glucose + 100 g of water. The density of water is 1.00 g/ml

    10. Examples Determine the mass of sodium hydroxide, NaOH, required to prepare 250.0 grams of a solution that is 8.00% NaOH by mass. Calculate the mass of 8.00% NaOH solution that contains 32.0 grams of NaOH. Calculate the mass of NaOH in 300.0mL of 8.00% NaOH solution. The density of the solution is 1.09g/mL.

    14. Examples What volume of 12.9% KOH solution contains 40.0 grams of KOH? The density of the solution is 1.11g/mL.

    16. Molarity Moles of solute per liter of solution M = moles of solute liters of solution Abbreviate: mol/L A 2.0M (molar) solution of NaCl contains 2.0 moles of NaCl in 1.0 liter of solution. Or 4.0 moles of NaCl in 2.0 liters of solution etc.

    18. Examples Calculate the molarity of a solution prepared by dissolving 12.5 g of sulfuric acid (H2SO4) in sufficient water to give 1.75L of solution. Determine the mass of Ca(NO3)2 required to prepare 3.50 L of a solution that is 0.800M in Ca(NO3)2.

    21. Examples The density of commercial hydrochloric acid is 1.185g/mL. It is 36.31% HCl by mass. Determine its molarity.

    24. Using Solutions in Chemical Reactions Na2SO4 + BaCl2 ? BaSO4 + 2NaCl Determine the volume of 0.500M BaCl2 solution required for complete reaction with 4.32g of Na2SO4 according to the reaction

    26. Using Solutions in Chemical Reactions: Titration The process, operation, or method of determining the concentration of a substance in solution by adding to it a standard reagent of known concentration in carefully measured amounts until a reaction of definite and known proportion is completed, as shown by a color change or by electrical measurement, and then calculating the unknown concentration.

    27. Dilution of Solutions A more concentrated solution can be diluted with solvent to produce a solution that is more dilute. The moles of solute will be the same in both solutions. However, since the volumes will be different the molarity will change. M1V1 = M2V2

    28. Examples Determine the volume of 18.0M H2SO4 required to prepare 2.50 liters of 2.40M H2SO4 solution. If 50.0 ml of 12.0M HCl is diluted to a final total volume of 200.0 ml, determine the final concentration of the solution.

    31. Molality Moles of solute per kilogram of solvent m = moles of solute kg of solvent A 1.0m (molal) solution of NaCl contains 1.0 moles of NaCl in 1.0 kg of water.

    33. Examples Determine the molality of a solution prepared by dissolving 400 g of NaOH in 500mL of water. The density of water is 1.00g/mL. M.W. of NaOH is 40.0 amu. Calculate the molarity and molality of an aqueous solution that is 10.0% glucose. The density of the solution is 1.04g/mL. M.W. of glucose = 180.0amu.

    36. Examples Determine the molality of a solution that contains 7.25 g of benzoic acid, C6H5COOH, in 200 mL of benzene, C6H6. The density of benzene is 0.879g/mL and the molar mass of benzoic acid = 122 amu.

    38. Mole Fraction Moles of component A per total moles of all components in the solution. XA = molesA molesA + molesB + molesC XB = XA + XB + XC + ……… = 1

    39. Examples What are the mole fractions of glucose and water in 10.0% glucose solution.

More Related