1 / 13

As you come in,

As you come in,. Pass up the Calories in a Chip Lab. Get paper, pencil, and calculator ready for notes on calculations. NOTE: Solubility Graph Quiz tomorrow!. Concentration. Concentration - the amount of solute in a specific amount of solvent Molarity ( M ) Molality ( m )

Télécharger la présentation

As you come in,

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. As you come in, • Pass up the Calories in a Chip Lab. • Get paper, pencil, and calculator ready for notes on calculations. • NOTE: Solubility Graph Quiz tomorrow!

  2. Concentration • Concentration - the amount of solute in a specific amount of solvent • Molarity (M) • Molality (m) • Molarity is the most common unit used to report the concentration of a solution in a laboratory setting.

  3. Molarity • The number of moles of solute per liter of solution. • Write a mathematical equation to represent the definition of molarity. • Explain your equation. (A) • Agree or disagree. (B)

  4. Molarity Equation moles of solute Molarity = Liters of solution Example: Calculate the molarity of 0.4 mol NaCl dissolved in 1.6 L solution. Answer: 0.25 M NaCl

  5. 5 minute Independent Practice • You will have a 5 minute Partner time next. 8-) Practice Problems: • 20.2 grams of potassium nitrate is dissolved in enough water to make 250.0 mL of solution. What is the molarity? • Calculate the number of grams of solute needed to prepare 2.0 L of 2.0M nitric acid. • Challenge: Give the concentrations of all the ions in each of the following solutions: • 0.50M Co(NO3)2 • 1 M FeCl3

  6. 5 Minute Partner Review • Check your Practice Problem answers with your partner. • Are your chemical formulas written correctly? • Did you make the appropriate conversions before plugging into the molarity equation? • What are your questions? (Write them down, and prepare to ask with our large group.)

  7. Molarity - Correct Answers • Potassium nitrate = KNO3 20.2 g KNO3 is converted to 0.20 mol KNO3. The volume of 250.0mL is converted to .250L. The Molarity = 0.8 M KNO3 • Nitric Acid = HNO3 4mol of HNO3 is calculated by plugging into the Molarity equation. The mass of four moles of HNO3 is 252 grams.

  8. Molality • The number of moles of solute per kilogram of solvent. • Write a mathematical equation to represent the definition of molality. • Explain your equation. (B) • Agree or disagree. (A)

  9. Molality Equation moles of solute Molality = kilograms of solvent Example: What is the molality of a solution that contains 2.3 moles of glucose dissolved in 500.0 g of water? Answer: 4.6 m

  10. 5 Minute Independent Practice • Practice Problems: • Find the molality of 131 g Ba(NO3)2 dissolved in 750.0 g H2O. • How many grams of sodium chloride must dissolve in 750.0 grams of water to make a 0.50 molal solution?

  11. Molality - Correct Answers • 131 g Ba(NO3)2 is converted to 0.50 moles, and 750.0 g of H2O is converted to 0.750 kg H2O. The molality is 0.67 m Ba(NO3)2. • 750.0 grams of H2O is converted to 0.750 kg of H2O. The equation is solved to give 0.375 moles NaCl, which converts to 21.9 grams.

  12. Preparing a Solution Lab • Today, you will be writing a lab procedure to prepare a solution of a specific Molarity. • Purpose • Materials • Procedure • Calculations • Each group will be preparing a different solution.

More Related