Chapter 8 Solutions, Acids, and Bases. 8-1 Formation of Solutions Substance can dissolve in water three ways-by ___________, ____________, and_________.

Chapter 8Chapter 8Chapter 8Chapter 8

Solutions, Acids, and BasesSolutions, Acids, and Bases

8-1 Formation of Solutions

• Substance can dissolve in water three ways-by ___________, ____________, and_________

• A ____________ is a substance whose particles are dissolved in a solution.

• The substance in which the solute dissolves is called the __________.

• Ex: Seawater• Solute = is the_________• Solvent = is the___________

Solutes/Solvents• Solutes and solvents can take the

form of a _________, ________ or ______

• The solution takes the_________ of the solvent.

Dissociation of Ionic Compounds

• ______________ is the process in which an ionic compound separates into ions as it dissolves.

• For a solute to dissolve in water, the solute and solvent particles must________ one another.

• Before a _________ can form, the attractions that hold the solute together and the solvent together must be ___________

Dispersion of Molecular Compounds

• Sugar dissolves in water by _______, or breaking into small pieces that spread throughout the water.

• Ex: piece of ________ disperses throughout your mouth

• _______ in saliva dissolves the________ and flavoring in the candy.

Process of Dispersion• When enough ________molecules

surround a sugar molecule, the attractions between them are great enough to overcome the attractions holding the _______ molecule to the surface of the crystal.

• The sugar molecule ________ free, and is pulled into solution by the water molecules, then another layer if sugar molecules is exposed to the water

Ionization of Molecular Compounds

• The process in which neutral molecules gain or lose electrons is known as _____________.

• Dissolving by ionization is a _________ change.

• The solution that results contains______ substances.

• When a solute dissolves by ionization, the ions in solution are formed by the reaction of _______ and _________ particles.

Example of Ionization• When _______ and____________form

a solution, two molecular compounds react to form two ions.

• Ions formed are H3O+ and Cl-

• Drawing

Answer the following Questions

1. What are three ways that substances can dissolve in water?

2. How does sugar dissolve in water?

8-1 ContinuedProperties of Liquid

solutions• Three physical properties of a

solution that can differ from those of its solute and solvent are:

1. _____________2. _____________3. _____________

Conductivity• _______ sodium chloride is a

_______ conductor of electricity• Sodium chloride _________ in water

and the ions formed can move freely enabling them to_________ electricity

Freezing Point• The __________ point of water at sea

level is 0 degrees Celsius

• Example : icy roads are salted with magnesium chloride, the resulting solution can have a freezing point as low as __________degrees Celsius

Boiling Point• A _________ can raise the boiling point of

the solvent

• Example: the __________ used in most car radiators is a solution containing water and ethylene, which raises the boiling point. This helps the engine from ____________.

Heat of Solution• During the formation of a solution,

energy is either _________ or __________.• In order for a solution to form, both the

attractions among the _______ particles and the attractions among the _______ particles must be_________

• _________ attractions________ energy.

Heat of Solution Continued

• As the solute dissolves, new attractions _________ between solute and solvent particles.

• The___________ of attractions __________energy.

• The difference between these energies is known as____________

Factors Affecting Rates of Dissolving

• Factors that affect the rate of dissolving include:

• _________• __________• __________

Surface Area• The ________ the surface area of a

solid solute, the more frequent the __________ are between solute and solvent particles.

• More collisions result in________ rate of dissolving

Stirring• __________ moves dissolved

particles away from the surface of the solid, and allows for more collisions between the solute and solvent particles

Temperature• _________ the temperature of the

solvent _________ up the dissolving rate.• This causes its particles to move faster.• As a result, both the number of

collisions and the __________ of these collisions with solute particles increase.

• The ________ goes into the________ more quickly.

Section 8-1 Review• Using your book complete the

following questions:• Page 257 • Numbers 1,2,3,4,5

Section 8-2• The maximum amount of a solute that

dissolves in a given amount of solvent at a constant temperature is called___________

• Ex: _______ in lemonade• Knowing the solubility of a substance

can help you classify solutions based on how much _________ they contain.

Solubility• Solutions are described as:• ___________, • ___________,• ___________• depending on the amount of______

in solution.

Saturated Solutions• Table sugar is very _________ in water• A _________ solution is one that contains

as much solute as the solvent can hold at a given temperature.

• When a solution is saturated, the solvent is “_________” with solute.

• If you add more solute, it will___dissolve.

Unsaturated Solutions• A solution that has______ than the

maximum amount of solute that can be dissolved is called an _________ solution.

• Example: many_________ you drink are unsaturated solutions of sugar in water.

• As long as the amount of solute is less than the___________at that temperature, the solution is _________

Supersaturated Solutions

• A____________ solution is one that contains more solute than it can normally hold at a given temperature.

• Supersaturated solutions are very __________.

• Ex: Carrying a stack of________

Review Questions• What terms are used to describe

solutions with different amounts of solute.

• How does a supersaturated solution differ from a saturated solution?

How Cold Packs Work• Read page 233 in your book

• Discussion

8-2 Continued• Factors Affecting Solubility• Three factors that affect the

solubility of a solute are:1. _________________2. _________________3. _________________

Polar and Nonpolar Solvents

• Oil does not dissolve in water because oil molecules are_______ and water molecules are ________

• A common guideline for predicting solubility is “like ________like”

• __________ formation is more likely to happen when the solute and solvent are either both polar or both nonpolar

Temperature• In general, the solubility of solids________

as the solvent temperature ___________.• Example: sugar added to______tea

verses _____tea

• _______usually become less soluble as the temperature of the solvent increases

Pressure• _______ the _______ on a gas________ its

solubility in a liquid• Carbonated beverages, uses pressure

to force CO2 to dissolve in the liquid

• The _______ of CO2 in a sealed 12-ounce can of soda at room temp can be two to three times atmospheric__________.

Concentrations of Solutions

• The __________ of a solution is the amount of solute ________in a specified amount of solution

• Concentrations can be expressed as percent by ________, percent by________, and________.

Percent by Volume• Percent by Volume = Volume of solute x

100%• Volume of solventExample the volume of the solute is 10 L and

the volume of the solvent is 30 L. What is the percent by volume?

Percent by Mass• Concentration expressed as a

percent by mass is ________ useful when the solute is a solid.

• Percent by mass = Mass of solute x 100%• Mass of solution• Example: Suppose you have 100grams of a

solution of sugar in water. After allowing the water to evaporate, 15 grams of sugar remains. What is the percent by mass?

Molarity________ is the number of moles of a

solute dissolved per liter of a solution.

• Molarity = moles of solute x 100%

• Liters of solution

Example of Molarity• To make 1-molar (_____) of solution of

sodium chloride in water1. First calculate the molar mass of the

solute (NaCl) = _________2. If 58.5 grams of sodium chloride is

mixed with enough water to make_________ of solution, the resulting solution is 1-molar.

Complete the following Questions

• Page 239 questions 1,2,3,4

8-3 Properties of Acids and Bases

• There are several differences among _______solutions, ______solutions, and solutions that have properties________ an acid or nor a base

Identifying Acids• An ________is a compound that

produces hydronium ions (_____) when dissolved in water.

• Ex: HCl + H2O H3O+ + Cl-

• Some general properties of acids include _________, ________ with metals, and ability to produce ________________

Sour Taste• Foods that taste _______ often contain

acids• Ex: ________, grapefruits, limes, and

________ all contain________acid.• _______contains ________ acid.• _______ products that have______contain

______ acid

Reactivity with Metals• When you use _______ foil to cover

a bowl of leftover spaghetti sauce or other foods containing________ the foil often turns_______.

• ________contain _______acid, which _________ with metals such as aluminum

Reactivity with Metals• The reaction between an acid and a

metal is an example of _______ replacement reaction.

• Ex: ______ is added to hydrochloric acid. • Zn +2HCl H2 + ZnCl2• As zinc replaces hydrogen in

hydrochloric acid, ________ gas and____________ is produced

Color Changes in Indicators

• An __________ is any substance that changes color in the presence of an _____ or_______.

• One of the most common indicators used is________, a kind of_______ derived from plants called lichens.

• Litmus________is made by coating strips of paper with litmus.

• _______litmus paper turns________in the presence of an _____.

Testing Acids on litmus paper

• Observations• Vinegar –

• HCl –

• Sulfuric Acid-

• Acetic Acid -

Identifying Bases• Sodium hydroxide, ________ is an

example of a base.• A _______ is a compound that

produces hydroxide (_____) when dissolved in water.

• _______ Na+ + OH-

Bases• ______ have certain______ and

________ properties that you can use to identify them.

• Some general properties of bases include ________, _______, and ability to produce ___________ in indicators

Properties of Bases• ____________• ____________• _____________________

Bitter Taste• ______ chocolate (without the

sugar)• Cough___________ and other liquid

medicines

Slippery Feel• Bases feel ______.• Wet ________ and

many___________products that contain bases are slippery to the touch.

• When wet, some ________ feel slippery because water dissolves compounds trapped in the rocks, producing a basic solution.

Color changes in Indicators

• Bases turn_____litmus paper_____.• Observations of bases• NaOH –

• Ba(OH)2-

• NH4OH-

Flowers• Hydrangeas color changes based

on whether they are grown in acidic or basic soil

• Acidic – flowers are bluish-purple

• Basic – flowers are pink

End of 8-3Neutralization and

Salts• _______contains bases that can leave a

bitter taste.• Lemon juice contains an______called

citric acid.• Squeezing lemon juice on fish makes it

taste ________bitter• The reaction between an acid and a

base is called _____________

Neutralization• During neutralization, the_________ ions in an

______ combine with the_________ions in a ________to produce an ionic compound called a ______

• The hydronium ions from the acid combine with the hydroxide ions from the base to produce__________.

• The neutralization reaction between an acid and a base produces a________and__________.

Example of neutralization

• (H3O+ + Cl- ) + Na+ + OH- ) 2HOH + (Na+ + Cl-)

_____ _______ _______ _____

Other common salts that are produced during neutralization are:

1. Potassium chloride – ______ – salt substitute

2. Potassium iodide – ______- added to table salt to prevent iodine deficiency

3. Magnesium Chloride –_______ – De-icer for roads

Proton Donors and Acceptors

• Acids lose or “_______” protons• Bases “_______” protons, forming water,

a neutral molecule.• ______can be defined as proton _____,

and _______ can be defined as proton _________.

• Example_______can act either as an acid or base depending on the compound with which it reacts.

Water acting as an acid and a base

• Complete the following examples from the board.

8-4Strengths of Acids and

Bases• Chemists use a number scale from

_______ to______to describe the concentration of __________ ions in a solution. It is known as the_____________.

• The _______of a solution is a measure of its hydronium ion concentration.

pH scale• A pH of _____indicates a ______

solution.• ______ have a pH______ than 7• _______have a pH______than 7• See Figure 22

pH scale• ______ is neutral because it contains

small but ________ concentrations of hydronium ions and hydroxide ions.

• The _______the pH value, the_______ the H3O+ ion concentration in solution is.

• The ________ the pH value, the______ the H3O+ ion concentration is.

Strong Acids and Bases• When certain acids and bases

dissolve in water, the formation of ions from the solute______ goes to ________. Such acids and bases are classified as _______.

Strong Acids• When strong ________ dissolve in

water, they ionize almost completely.

• Ex: _______= hydrochloric acid

• _______ = sulfuric acid

• _______ = nitric acid

Strong Bases• Strong________ dissociate almost

completely in water.• Examples of strong bases:________ – sodium hydroxide________ - calcium hydroxide________ – potassium hydroxide

Beaker Breaker1. Acids have a pH range from ________to

___________

2. Name one property of a base _______________

3. Compare the pH values of acids, bases, and pure water.

Weak Acids and Bases• Weak ______ and_______ ionize or

dissociate only ________ in water• The citric acid in orange

________and the acetic acid in_________ are_________acids.

• __________and________ contain weak ________.

Concentration verses strength

• ___________ is the amount of solute dissolved in a given amount of solution.

• _________ refers to the solute’s tendency to form ions in water.

Weak Acids• A weak acid forms ________

hydronium ions than a strong acid of the same concentration.

• A weak acid has a ________ pH than a strong acid of the same concentration.

Weak Bases• Follows the same concept as weak

acids.

• Example is NH3 (ammonia) because when it dissolves in water, very little of it_________.

Buffers• Weak acids and bases can be used

to make ___________. • A ________ is a solution that is

___________to large changes in pH. • Buffers can be prepared by_______

a _______acid and its______or a ________ base and its _______.

Electrolytes• An __________ is a substance that

ionizes or dissociates into ions when it dissolves in water.

• The resulting solution can conduct__________ current.

• Electrolytes in sports drinks help _____________the balance of ions in your body.

Electrolytes• Strong acids and bases are strong

electrolytes because they dissociate or ionize almost__________ in water.

• Ex: sodium hydroxide (______) is a strong ___________ that produces many ions in water.

• Acetic acid is a weak electrolyte because it only________ ionizes.

Examples of Electrolytes

• _____________ and other portable devices that produce electricity also contain electrolytes.

• _______batteries use lead plates in combination with the electrolyte sulfuric acid to produce _________.

• Space shuttles use devices called________• Fuel cells use the strong _______ potassium

hydroxide as an electrolyte.

Testing strong weak acids verses strong weak bases

on litmus paper• Observations

Test #1

Test #2

Test# 3

Test#4