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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