Chapter 12: Solutions

1. Read Ch12.1-12.2 (pg 400-414.)– Title the notes “Ch 12 Solutions” (in notes section)

– Copy table 1 pg 402 *summarize/abbreviate as possible

– Table 2 pg 404– Table 3 pg 404– Read and take notes/ create vocab list

2. Materials, Procedures and Hypothesis for final science fair project: Due Friday– Pg 5 and 6 of packet

3. Get PhET activity to start (Friday activity, due next Monday)

Goals:

Section 1- Types of Mixtures

• Solutions are homogeneous mixtures of two or more substances in a single phase.

– Soluble describes a substance as capable of being dissolved.

– Solvent is the dissolving medium in a solution.

– Solute is the substance that is dissolved in a solution.

Types of Solutions

• Solutions can be in any of the three common physical states.

solid- a mixture of metals called an alloy

liquid- salt water, sugar water, Kool-Aid…

gas- the atmosphere

Suspensions & Colloids

• A suspension has large particles that settle out of a solvent. ex. muddy water

• A colloid has intermediate size particles. Also called an emulsion or a foam.

Solutes: electrolytes vs. nonelectrolytes

• An electrolyte is a substance that dissolves in water to give a solution that conducts electricity.

• A nonelectrolyte is a substance that dissolves in water to give a solution that does NOT conduct electricity.

Ch 12.2- The Solution Process

• Factors that affect the rate of solution (how quickly a substance dissolves):– Any process that increases the number of

contacts between the solvent and the solute will increase the solution rate.

• increasing the surface area of the solute• agitating (shaking or stirring) the solution• heating the solvent

Graphs

Dependant variable(units)

independent variable (units)

All Graphs Need:TitleLabeled axisUnits as needed

Title

Key:

Warm up:

1. Compare and contrast molarity and molality.

2. If given or asked for grams, how do you relate grams to moles?

Ex C: Suppose you want to dissolve 205g of Na2CO3 in enough water to make 5.00L of solution. What is the molarity? • Molar mass= 106.0g/mol

• 205/106 =

Solubility Vocab• Solubility is a measurement of how much solute will dissolve in a specific

amount of solvent at a specific temperature to make a saturated solution.

• “Likes dissolve likes”- polar solvents dissolve polar solutes & nonpolar solvents dissolve nonpolar solutes.

• Hydration: the solution process with water as the solvent.

• Hydrates: ionic compounds that have formed crystals that have incorporated water molecules in their structure.

• Immiscible liquids are not soluble in one another. eg. oil & water

• Miscible liquids dissolve freely in one another in any proportion. eg. water & alcohol

Solutions• Solution equilibrium: the physical state

in which the opposing processes of dissolution and crystallization occur at equal rates.– Dissolution: dissolve– Crystallization: form solid

Factors that affect the rate of solution: (how quickly a substance dissolves)– Any process that increases the number of contacts

between the solvent and the solute will increase the solution rate.

– Increase solution rate by:• increasing the surface area of the solute• agitating (shaking or stirring) the solution• heating the solvent

temp. and pressure affects on solubility:

•Increasing the pressure increases the solubility of gases in a liquid.

– has no effect on the solubility of a solid in a liquid

• For solid in liquid, increasing temperature often increases the solubility

• For gas in liquid, increasing temp decreases the solubility.

• Henry’s Law: the solubility of a gas in a liquid is directly proportional to the partial pressure of the gas on the surface of the liquid.

• Effervescence is the rapid escape of a gas from a liquid in which the gas is dissolved.

• A solvated solute particle is surrounded by solvent molecules.

• saturated solution: contains the maximum amount of dissolved solute.

• unsaturated solution: contains less than the maximum amount of dissolved solute.

• A supersaturated solution: contains more dissolved solute than a saturated solution.

Solubility curve

Solubility is a measurement of how much solute will dissolve in a specific amount of solvent at a specific temperature to make a saturated solution.

Will the solubility increase, decrease, remain the same?

1. Soda is opened and heated (the gas)?2. Solid sodium chloride is dissolved is water as it

is heated. 3. Carbon dioxide is dissolved in water as it is

cooled. 4. Potassium chloride is added to a saturated

solution. 5. The surface pressure of salt water is increased. 6. Surface pressure of dissolved oxygen is

increased.

1. Decrease2. Increase3. Increase4. Same5. Same6. increase

• Enthalpy of solution: amount of heat absorbed by a solution when a specific amount of solute dissolves in a solvent.

Classwork1. Solutions Matching• Put in classwork section, number your page

and write out the vocab word for answers

2. When done, work on solutions PHeT simulation (see handout section of website)

3. Then work on study guide

ClassworkSolutions Matching

•Put in classwork section, number your page and write out the vocab word for answers

Ch 12.3 Practice C and E

•Answer questions:– Pg 421 Practice #1-3– Pg 424 Practice #1-2

•Solutions on pg 920

1.Solutions2.Soluble3.Solvent4.Solute5.Nonelectrolyte6.miscible7.Colloid8.Suspension9.Supersaturated10.Saturated11.unsaturated12.Electrolyte13.Solubility14. immiscible

B. 1.Solute2.Immiscible3.Colloid4.Solution, miscible5.Saturated6.Electrolyte7.Solvent8.suspension

12.3Concentrations of Solutions

• The concentration measure of the amount of solute dissolved in a given amount of solvent or solution.

• Molarity (M) is the number of moles of solute in one liter of solution.

M = #mol L

• Do practice problems #1, #2, & #3 on page 421.

Warm up:

1. What is a solution?

2. A solute?

3. A solvent?

12.3Concentrations of Solutions

• Molarity (M) is the number of moles of solute in one liter of solution.

M = mol LEx A: pg 420What is the molarity of a 3.50L solution that contains 90.0g of NaCl

Molar mass = 58.44g/mol90.0g x (1mol/58.44g) = 1.54 mol

1.54 mol = .440 M NaCl3.50 L

Ex B:How many moles of HCl in 0.8L of a 0.5M

solution?

M = mol .5M = mol

L .8L

.8L(.5mol/L) = .4mol HCl

• Molality (m) is the concentration of a solution expressed in moles of solute per kilogram of solvent.

m = mol

kgEx D: pg 423A solution dissolved .0500mol C12H22O11 in 125g of water, what

is the molal concentration?

125g (1kg/1000g) = .125kg

.0500 mol = .400 m C12H22O11 .125kg

•Read Ch12.1-12.2 (pg 400-412.) and take notes in note section of notebook.

– Title the notes “Ch 12 Solutions” – Copy table 1 pg 401– Table 2 pg 404– Table 3 pg 404– Create a vocab list

Graphs

Dependant variable(units)

independent variable (units)

All Graphs Need:TitleLabeled axisUnits as needed

Title

Key:

What are the independent and dependent variables? What is the saturation point of the blue chemical? What unit is used to measure saturation?

Solubility curve

Solubility is a measurement of how much solute will dissolve in a specific amount of solvent at a specific temperature to make a saturated solution.

Solution Concentrations

• Percent composition by mass (%) is a concentration that expresses the percent of solute in a solution.

% = #g solute x 100

# g solution

matching1. homogeneous mixtures of two or more substances in

a single phase.2. describes a substance as capable of being

dissolved.3. the dissolving medium in a solution.4. the substance that is dissolved in a solution.5. Doe not conduct electricity6. Liquids that dissolve freely in one another7. intermediate size particles, also called an emulsion

or a foam8. large particles that settle out of a solvent. 9. Contains more dissolved solute than saturated

solution under same conditions10. Solution containing maximum amount of dissolved

solute11. Contains less solute than possible under the existing

conditions12. Conducts electricity13. Amount of substance to form a saturated solution

under specific conditions14. Liquids that are not soluble in each other

a. Solubleb. Solventc. Soluted. Solutionse. Solubility f. Electrolyteg. Nonelectrolyteh. Immisciblei. Misciblej. Suspentionk. Saturated l. Unsaturatedm. Supersaturatedn. Colloid

1. Solutions2. Soluble3. Solvent4. Solute5. Nonelectrolyte6. miscible7. Colloid8. Suspension9. Supersaturated10.Saturated11.unsaturated12.Electrolyte13.Solubility14. immiscible

Chapter 12 Test Review

• multiple choice – define & identify suspensions & solutions– define an alloy– define & identify electrolytes & nonelectrolytes– factors that affect the rate of dissolution– definitions of unsaturated, saturated & supersaturated solutions– general rules for predicting whether a solute is soluble in a

solvent– definition of solubility– effects of temperature & pressure on the solubility of gases and

solids in liquids– definitions of molarity (M) and molality (m)– solving molarity & molality problems– FORMULAS: M = #mol/L m = #mol/kg