TOPICS TO BE COVERED

1.WHAT ARE SOLUTIONS?

2.SOLVENTS AND SOLUTES

3.SOLUBILITY AND ITS FACTORS

4.CONCENTRATIONS

5.SOLUTION STOICHIOMETRY

6.COLLIGATIVE PROPERTIES

SOLUTIONSCHEMICALS + WATER

1. WHAT ARE SOLUTIONSOBJECTIVE: WHAT ARE THEY?

SOLUTIONS

• IMPORTANCE OF STUDYING SOLUTIONS

• BECAUSE MANY REACTIONS TAKE PLACE IN SOLUTIONS

• BECAUSE MIXING REACTANTS IN SOLID FORM OFTEN DO NOT RESULT IN REACTIONS.

• REACTIONS REQUIRE COLLISIONS AT THE ATOMIC/MOLECULAR LEVEL, AND IN THE SOLID STATE, THIS DOES NOT OCCUR AT A SIGNIFICANT RATE.

1. WHAT ARE SOLUTIONS?

SOLUTIONS ARE…

HOMOGENOUS MIXTURES

• HOMOGENOUS VS. HETEROGENEOUS

• MIXTURE VS. COMPOUND

1. WHAT ARE SOLUTIONS?

HOMOGENEOUS

EVEN DISTRIBUTION

HETEROGENEOUS

UNEVEN DISTRIBUTION

1. WHAT ARE SOLUTIONS?

MIXTURES

PHYSICALLY

MIXED

COMPOUND

CHEMICALLY

JOINED

SOLUTIONS

1. WHAT ARE SOLUTIONS?

MIXTURES

CAN BE SEPARATED

COMPOUND

CANNOT

BE SEPARATED

1. WHAT ARE SOLUTIONS?

MIXTURES

CAN BE SEPARATED

COMPOUND

CANNOT

BE SEPARATED

1. WHAT ARE SOLUTIONS?

SOLUTIONS ARE…

HOMOGENOUS MIXTURES

SOLUTIONS = TWO OR MORE THINGS EVENLY

MIXED TOGETHER

SOLUTIONS = THINGS MIXED INTO WATER

1. WHAT ARE SOLUTIONS?

HETEROGENEOUS MIXTURES:

SUSPENSIONS & COLLOIDS

Suspensions

Separates and Settles Colloids do not

Jello or Milk

2. SOLUTES AND SOLVENTSOBJECTIVE: CLASSIFYING INGREDIENTS IN

SOLUTIONS

2. SOLVENT AND SOLUTE

All solutions have at least TWO ingredients

Ingredients can be classified as either a

SOLVENT

SOLUTE

2. SOLVENT AND SOLUTE

SOLVENT- PRESENT IN GREATER AMOUNT

- DOES THE “DISSOLVING”

WATER IS THE UNIVERSAL SOLVENT

SOLUTE- PRESENT IN LESSER AMOUNT

- IS THE ONE “DISSOLVED”

2. SOLVENT AND SOLUTE

Does not always involve liquids

2. SOLVENT AND SOLUTECAN THERE BE MORE THAN ONE SOLUTE IN A

SOLUTION?

CAN THERE BE MORE THAN ONE SOLVENT IN A SOLUTION?

IF A SOLUTION IS A MIXTURE, DO THE SOLUTES AND THE SOLVENTS CHEMICALLY REACT OR PHYSICALLY MIX?

3. SOLUBILITYOBJECTIVE: IF SOMETHING DOES OR DOES NOT

DISSOLVE

3. SOLUBILITY

Why do some things dissolve while others do not?

What does it mean for something to “dissolve?”

3. SOLUBILITY

Why do some things dissolve while others do not?

“Like dissolves Like”

3. SOLUBILITY

“Like dissolves Like”

Polar Solvent will dissolve…

Non-Polar Solvent will dissolve

3. SOLUBILITY

Miscible vs. Immiscible

Miscible = dissolves

Immiscible = does NOT dissolve

3. SOLUBILITY

What does it mean for something to “dissolve?”

It means to “dissociate”

Dissociation

Separating

dipoles

3. SOLUBILITY

Now we know why some things dissolve and others do not.

We also know what it means for something to dissolve.

3. SOLUBILITY

How much of some thing can be dissolved?

SolubilityTHE MAXIMUM AMOUNT OF A SOLUTE THAT CAN

DISSOLVE AT A SPECIFIED TEMPERATURE AND PRESSURE

3. SOLUBILITY

Increasing/Decreasing Solubility

1. Temperature

2. Pressure

3. SOLUBILITY

WHAT IS THE

TREND?

SO AS TEMPERATUR

E _______, SOLUBILITY

______

3. SOLUBILITY

Increasing Solubility with Temperature

Unsaturated Solutions

more solute can be

dissolved

no heat necessary

Saturated Solutions

no more solute can be

dissolvedno heat necessary

Super-Saturated Solutions

more solute than normal

heat necessary

Super-Saturated Solutions

Rock Candy

GAS SOLUTE

AS TEMPERATURE _____ THE SOLUBILITY OF GAS _______.

SO TEMPERATURE AND SOLUBILITY OF A GAS HAVE

A(N) ____.

RECALLING HEAT AS KINETIC ENERGY, WE CAN EXPLAIN

THIS BY…

SOLUBILITY OF SOLIDS

SOLUBILITY OF GASES

1. EXPLAIN WHY THERE MIGHT BE MORE MINERAL FORMATION SURROUNDING THERMAL SPRINGS THAN COOL MOUNTAIN SPRINGS.

2. WHY DOES WARM SODA FLATTEN FASTER THAN COLD SODA?

3. ON SAME SHEET, ANSWER QUESTIONS #67-72 ON PG 491.

4. TURN IN

4. CONCENTRATIONSOBJECTIVE: MEASURING SOLUBILITY

4. CONCENTRATION

Concentration =

how much solute in

the solution

2 methods

4. CONCENTRATIONMolarity MOLALITY

Symbol

FormulaUnitsExample

4. CONCENTRATIONMolarity MOLALITY

Symbol MFormula

M = mol L

Units mol = mol of SOLUTE

L = liters of solution

Example

5 M, or 5 molar

4. CONCENTRATION

1.23 mol of HCl in solution

With volume of 5.00 L.

What is molartiy?

4. CONCENTRATION

3.45 M solution of AgCl is made with 2. 45 mol

of AgCl.

What is volume?

4. CONCENTRATION

3.45 M solution of AgCl is made with 2.45 L.

What is mol of AgCl?

4. CONCENTRATION

What are some signs that a chemical change

has taken place?

4. CONCENTRATION

Precipitate = a solid that forms

4. CONCENTRATION

Solution Stoichiometry

2 types

1. Molarity, then stoichiometry

2. Stoichiometry, then Molarity

4. CONCENTRATION

Solution Stoichiometry

Molarity mol mole ratio mol answer

4. CONCENTRATION

0.125 L of 0.100 M HCl is added to Zn. What mass

of ZnCl2 is formed?

Zn + 2HCl → ZnCl2 + H2

4. CONCENTRATION

Solution Stoichiometry

grams mol mole ratio mol Molarity

4. CONCENTRATION

11.0 g of Cu are needed. What volume of a 0.500 M solution of

CuSO4 is needed to result in

11.0 g of copper?

3CuSO4+ 2Al 3Cu + Al2(SO4)3

BA(NO3)2(AQ) + NA2SO4(AQ) BA(SO4)(S) + 2NANO3(AQ)

• 25ML OF 0.5M BA(NO3)2 SOLUTION IS COMBINED WITH EXCESS NA2SO4. HOW MANY GRAMS OF PRECIPITATE ARE FORMED?

CACL2(AQ) + 2NH4OH(AQ) CA(OH)2(S) + 2NH4CL(AQ)

• HOW MANY ML OF A 0.2M NH4OH

SOLUTION WOULD BE REQUIRED TO PRECIPITATE ALL OF THE CA2+

IONS IN 50ML OF A 0.15M CACL2

SOLUTION?

• SOLUBILITY OF GASES

• HENRY’S LAW

• AT A GIVEN TEMPERATURE, THE SOLUBILITY OF A GAS IN A LIQUID (S) IS DIRECTLY PROPORTIONAL TO THE PRESSURE OF THE GAS ABOVE THE LIQUID (P).

PB(NO3)2(AQ) + 2NACL(AQ) PBCL2(S) + 2NANO3(AQ)

• HOW MANY GRAMS OF PRECIPITATE WOULD FORM

IF 30ML OF A 0.25M PB(NO3)2 SOLUTION WAS

ADDED TO 20ML OF A 0.50M NACL SOLUTION?

• HOW MANY MOLES OF THE EXCESS REACTANT ARE LEFT OVER AFTER THE REACTION?

• WHAT IS THE MOLARITY OF THE EXCESS REACTANT AFTER THE REACTION?

CAN A SOLUTION WITH UNDISSOLVED SOLUTE BE

SUPERSATURATED?

• SOLUBILITY OF GASES

• HENRY’S LAW

• IF THE SOLUBILITY OF A GAS IN WATER IS 0.77G/L AT 350KPA OF PRESSURE, WHAT IS ITS SOLUBILITY, IN UNITS OF GRAMS/LITER, AT 100KPA?

• SOLUBILITY OF GASES

• HENRY’S LAW

• A GAS HAS A SOLUBILITY OF 3.6G/L AT A PRESSURE OF 100KPA. WHAT PRESSURE IS NEEDED TO PRODUCE AN AQUEOUS SOLUTION CONTAINING 9.5G/L OF THE SAME GAS?

• THE SOLUBILITY OF METHANE IN WATER AT 100KPA IS 0.026G/L, WHAT WILL THE SOLUBILITY BE AT A PRESSURE OF 180KPA?

• SOLUBILITY OF LIQUIDS

• LIKE DISSOLVES LIKE

• MISCIBLE – DESCRIBES TWO OR MORE LIQUIDS THAT ARE ABLE TO DISSOLVE INTO EACH OTHER

• IMMISCIBLE – DESCRIBES TWO OR MORE LIQUIDS THAT DO NOT MIX WITH EACH OTHER

• SOLUBILITY OF LIQUIDS

• LIKE DISSOLVES LIKE

• MISCIBLE

• NON-POLAR AND NON-POLAR = MISCIBLE

• POLAR + POLAR = MISCIBLE

• IMMISCIBLE

• NON-POLAR + POLAR = IMMISCIBLE

• PERCENT SOLUTIONS

• SIMILAR TO PPM

• PERCENT SOLUTIONS

• WHAT IS THE PERCENT BY VOLUME OF

ETHANOL (C2H6O) WHEN 75ML OF

ETHANOL IS DILUTED TO A VOLUME OF 250ML WITH WATER?

• A SOLUTION CONTAINS 2.7G OF CUSO4 IN 75ML OF SOLUTION. WHAT IS THE PERCENT BY MASS OF THE SOLUTION?

• CONCENTRATION OF IONS

• CALCULATE THE NUMBER OF MOLES OF CL- IN 2.75 L OF 1.0X10-3M ZNCL2

• HOW MANY GRAMS OF SULFATE ION ARE PRESENT IN 500ML OF A 2M AL2(SO4)3 SOLUTION?

5. COLLIGATIVE PROPERTIES

OBJECTIVE: CHANGING BOILING AND FREEZING POINTS

• COLLIGATIVE PROPERTIES

• THE PHYSICAL PROPERTIES OF A SOLUTION ARE DIFFERENT FROM THOSE OF A PURE SOLVENT.

• SOME OF THESE DIFFERENCES ARE DUE TO THE PRESENCE OF SOLUTE PARTICLES IN THE SOLUTION.

• COLLIGATIVE PROPERTIES

• COLLIGATIVE PROPERTIES – A PROPERTY OF A SOLUTION THAT DEPENDS ON THE CONCENTRATION OF THE SOLUTE PARTICLES.

• THE WORD COLLIGATIVE IS DERIVED FROM THE LATIN COLLIGATUS MEANING BOUND TOGETHER, SINCE THESE PROPERTIES ARE BOUND TOGETHER BY THE FACT THAT THEY ALL DEPEND ON THE NUMBER OF SOLUTE PARTICLES.

• COLLIGATIVE PROPERTIES

• BOILING POINT ELEVATION – THE DIFFERENCE IN TEMPERATURE BETWEEN THE BOILING POINTS OF A SOLUTION AND OF THE PURE SOLVENT.

• FREEZING POINT DEPRESSION – IS THE DIFFERENCE IN TEMPERATURE BETWEEN THE FREEZING POINTS OF A SOLUTION AND OF THE PURE SOLVENT.

• COLLIGATIVE PROPERTIES

• THE MAGNITUDE OF BP ELEVATION AND FP DEPRESSIONS IS PROPORTIONAL TO THE NUMBER OF SOLUTE PARTICLES DISSOLVED IN THE SOLVENT.

• COLLIGATIVE PROPERTIES

• WOULD A DILUTE OR CONCENTRATED SODIUM FLUORIDE SOLUTION HAVE A HIGHER BOILING POINT?

• IF EQUAL NUMBER OF MOLES OF KI AND MGF2

ARE DISSOLVED IN EQUAL AMOUNTS OF WATER, WHICH SOLUTION WOULD HAVE THE HIGHEST:

• BOILING POINT

• FREEZING POINT

MOLARITY MOLALITY

• VOLUME OF SOLUTE +

• VOLUME OF SOLVENT

• UNIT = M

BOTH MOLARITY AND MOLALITY MEASURE CONCENTRATION

• MASS OF SOLVENT IN KILOGRAMS

• UNIT = M (ITALICIZED)

• CALCULATING MOLALITY

• CALCULATE THE MOLALITY AND TOTAL MOLALITY (IF APPLICABLE) OF A SOLUTION PREPARED BY DISSOLIVING 10.0G OF NACL IN 600 G OF WATER.

• CALCULATE THE MOLALITY AND TOTAL MOLALITY (IF APPLICABLE) OF A SOLUTION

PREPARED BY DISSOLIVING 10.0G C12H22O11

OF IN 600 G OF WATER.

• CALCULATING MOLALITY

• HOW MANY GRAMS OF POTASSIUM IODIDE MUST BE DISSOLVED IN 500G OF WATER TO PRODUCE A 0.060 MOLAL KI SOLUTION?

• CALCULATING MOLALITY

• WHAT IS THE DIFFERENCE BETWEEN A 1M AND A 1M SOLUTION?

• A 4 G SUGAR CUBE (C12H22O11) IS

DISSOLVED IN A 350 ML TEACUP OF 80 °C WATER. WHAT IS THE MOLALITY OF THE SUGAR SOLUTION IF THE DENSITY OF WATER AT 80° = 0.975 G/ML

• CALCULATING BP AND FP CHANGES

• BP

•ΔTB = KB * M

• FP

•ΔTF = KF * M

• CALCULATING BP AND FP CHANGES

• KB, KF = THE MOLAL BP/FP CONSTANT,

WHICH IS EQUAL TO THE CHANGE IN BP/FP TEMPERATURE FOR A 1 MOLAL SOLUTION.

• CALCULATING BP AND FP CHANGES

• WHAT IS THE BOILING POINT OF A 1.5 MOL SOLUTION THAT IN 800G OF WATER?

• CALCULATING BP AND FP CHANGES

• WHAT IS THE BOILING POINT OF A 1.2 MOL SOLUTION OF NACL IN 800G OF WATER?

• CALCULATING BP AND FP CHANGES

• WHAT IS THE BP AND FP OF A 1.40 MOL

SOLUTION OF NA2SO4 IN 1750G OF WATER?

• DETERMINING MOLAR MASS FROM ΔTB AND ΔTF

• MOLAR MASS =

• 7.5 G OF SOLUTE IS ADDED TO 22.60 G OF WATER. THE WATER BOILS AT 100.78 DEGREES C. WHAT IS THE MOLAR MASS OF THE SOLUTE?