Chapter 16 Solutions

Flipped Classroom: • Your assignment for next class is to watch a video

and complete the quiz questions on the side and fill in the slides. – You need to go to sophia.org– Create an account (it is FREE) – Add my group with this code 3bac55– Click on chapter 16 solutions

• Then on solution vocabulary.

– While watching the video complete the notes. – Answer the three quiz questions on the side when

finished.

Solutions Vocabulary

• A solute is _____________________________ _____________________________________

• A solvent is ____________________________ _____________________________________

• Solubility refers to_______________________ _____________________________________

• An example is:

Solution Vocabulary

The __________________ is the usually the substance present in the greatest amount.

Solutions are considered ___________________ mixtures. This means:

Solutions Vocabulary

Not ALL solutions are made with solids dissolved in liquids! There are many types of solutions you can form. Complete the chart below:

Solute Solvent Example

Carbon Dioxide Water

Tin Copper

Iodine Alcohol

Oxygen Nitrogen

Definition of Concentration:

A solution: • _______________________________________

___________________________________Relative amounts of solutes dissolved in a solvent: • A __________ solution contains a relatively

small amount of solute. • A _______________ solution contains quite a

lot of solute

Definition of Concentration:

• ___________ and ___________ are ________________terms used to describe solutions

• A ________________ description does not provide numerical values for concentration.

Definition of Concentration

• Examples:

Molarity

• The concentration of a solution can be __________________ described by using molarity.

• Molarity is expressed by dividing the number of moles of the substance in the solution by the total volume of the solution

• The formula is written:

Molarity Calculations

• A solution is prepared by dissolving 60.0g of NaOH in 1.0 liters of distilled water. What is the molarity of solution?

Molarity Calculations

• If 57.5g of NaCl is dissolved in 1.5L of distilled water, what is the molarity of the solution?

NEW SLIDES

In CLASS

• ______________________- The maximum amount of substance that will dissolve at that temperature (usually g/L).

• _____________________________-Contains the maximum amount of solid dissolved.

• _____________________________- Can dissolve more solute.

• ____________________________- A solution that is temporarily holding more than it can

IN Class

M1 x V1 = M2 x V2 • 2.0 L of a 0.88 M solution are diluted to 3.8 L.

What is the new molarity?• Need 450 mL of 0.15 M NaOH. All you have

available is a 2.0 M stock solution of NaOH. How do you make the required solution?

Molality

• ________________ is a unit that can be used to express concentration of a solution.

• ________________ is best defined as the number of mole of a solute per 1.0 kg of solvent.

Equation:

Molality and molarity

• Molarity and molality are the two most common units used to express concentration of solution in chemisty. Unfortunately, they are VERY similar to each other.

• ________________ (M) is the number of moles of solute per LITER (L) of solution

• ________________(m) is the number of moles of solute per KILOGRAM (kg) of solvent

• _______________is required as a unit when calculating some other properties of solutions

Molality Calculations

A solution is created by dissolving 28.5g of NaCl in 1.0L of dissolved water. What is the molality of the solution?

Molality Calculations

An electrolyte solution contains 105.38 g of KCl (potassium chloride) dissolved in 500 mL of dissolved water. What is the molality of the solution? (Molar mass (MWT) of KCl=74.55 g/mol)

Colligative Properties

• When a solution is formed, the properties of the solution are affected. ________________ __________________________________________________________________________.

• The properties that change upon the formation of a solution are called colligative properties. These properties depend upon __________________________________________________________________________

Colligative properties

• An _____________ compound in w solution will cause a greater change in _____________ point, for example, because it seperates into _________ when it dissolves, creating even more particles in solution. (SALT)

• __________________ compounds do not have as great an effect, because when they dissolve the molecules stay together and do NOT break apart into smaller particles. (SUGAR)

Colligative properties

• Two most important colligative properties are the change in __________________________ and __________________________________

• __________________ point goes down (depression) and __________________ point goes up (elevation)

• Because the _________________ point of water changes when something is dissolved in water we can use a variety of chemical salts to __________ ice in the winter.

• This is a very practical application of chemistry, because it makes out roads and sidewalks safer to use!

Colligative Properties

• Because the boiling point goes up, we can add antifreeze to the water in radiator of our car to prevent it from boiling over in the hot summer months. (and prevent freezing in the cold winter months)

Calculating changes in Freezing and Boiling Points

• The formula for the change in freezing poin of a solution is:

Calculating changes in freezing point and boiling point

• What is the freezing point of a solution of 75.0g NaCl dissolved in 0.500L of water.

Calculating changes in freezing and boiling points

• The formula for the change in boiling point of a solution is:

Calculating changes in freezing point and boiling point

• What is the boiling point of a solution made by dissolving 750 g of sugar (C12H22O11) in 750 mL of water?