Chapter 6 : Solutions, Acids, & Bases

Solution Solute Solvent Concentration Molarity Suspension Colloid Acid Base Solubility

Types of Mixtures

Heterogeneous: not the same throughout

Homogeneous: uniform throughout (completely mixed)

Heterogeneous MixturesSuspensions: a mixture that

looks uniform when stirred or shaken that separates into different layers when it is no longer agitated.

Example: oil & vinegar , orange juice

Heterogeneous Mixtures Colloids: A mixture of very tiny

particles of pure substances that are dispersed in another substance but do not settle out of the substance.

Example: Jello

Particles in a colloid are much smaller than those in a suspension and do not settle at the bottom.

The particles stay dispersed throughout the mixture.

Heterogeneous Liquid-Liquid Mixtures

Liquids that will not dissolve into one another are Immiscible (they do not mix) Example: Oil & Vinegar

The oil is less dense & Floats above the vinegar

Emulsions Some immiscible liquids can mix in

emulsions. Example: Mayonnaise

An Emulsion is any mixture of immiscible liquids in which the liquids are spread throughout one another

Homogeneous MixturesUniform throughout

Example: Salt water

Solutions are homogeneous mixtures of two or more substances uniformly spread throughout a single phase

SolutionsThere are 2 main parts to a solution:

Solute: The substance that dissolves in a solution

Solvent: The substance that dissolves the solute to make a solution

Miscible Two or more liquids that form a

single layer when mixed are Miscible.

Miscible liquids can be separated by Distillation.

Chapter 6 Section 2: Dissolving & SolubilitySolutes with a larger surface area will dissolve faster.

Is dissolving a chemical change?

NO it is a Physical Change (pg. 60)

A substance in small pieces dissolves faster than the same substance in big pieces.

Stirring or shaking a solution helps the solute dissolve faster

“Movement” does what to the particles in a substance?

Adds energy which increases the speed of the particles

Solutes dissolve faster when the solvent is Hot

Not every substance dissolves

Substances can be Soluble and Partly Soluble

Soluble: dissolves in water

Partly Soluble: does not completely dissolve in water.

Water is the Universal Solvent!Water’s structure helps it dissolve charged particles.

Why? What is the structure of water?

Water is a polar molecule which allows it to dissolves substances easily

Like Dissolves Like

Water will not dissolve all substances.

Water cannot dissolve substances that are considered “nonpolar”

Concentration

The quantity of solute dissolved in a given a solution

Solutions can have different concentrations depending on the amount of solute & solvent

A solution that is dilute has a large amount of solvent compared to solute

A Concentrated Solution has a large amount of dissolved solute.

Unsaturated vs. Saturated Solutions

Unsaturated solutions can dissolve more solute.

They have more space available for particles to move (spread out).

Unsaturated vs. Saturated Solutions

*Considered “Unsaturated” as long as a solution can dissolve more solute.

Unsaturated vs. Saturated Solutions

A Saturated Solution is a solution that cannot dissolve any more solute at the given conditions

SolubilityThe greatest quantity of a solute that will dissolve in a given quantity of solvent to produce a saturated solution.

Heating a saturated solution usually allows you to dissolve even more solute.

The Solubility of most solutions will increase as the temperature increases.

Supersaturated solution!!A solution holding more dissolved solute than is specified by its solubility at a given temperature.

SupersaturatedSupersaturated solutions are unstable systems because the solute’s solubility is exceeded for a short time.

Measuring Concentration Precisely

Concentration can be measured/expressed in grams per 100g of solvent or as a mass percent or in grams per 100g of solution.

Measuring Concentration Precisely

Concentration can also be expressed in units of Molarity

Molarity: is a concentration unit of a solution that expresses moles of solute dissolved per liter of solution.

MolarityMolarity = moles of solute

liters of solution

*Molarity is the preferred concentration unit because it expresses the molar amount of solute present*

What are acids?

An Acid is a substance that creates hydrogen ions H+ ◦ will form Hydronium ions when dissolved in water.

Acids have a pH below 7

Indicators can be used to determine the acidity of a substance.

Litmus paper can be used as an acid indicator◦Acids will turn blue litmus paper red.

Acidic solutions have similar properties

Sour taste

Can burn skin or eyes

All acids can conduct electricity when dissolved in water because all acids for hydronium ions (H3O+).

Strong acids will conduct electricity better than weak acids

Ions created as acids dissolve in water move throughout the solution conducting electricity.

Sulfuric Acid in water conducts electricity in car batteries.

Weak acids do not ionize completely & will not conduct electricity

◦Example: Acetic Acid (Vinegar)

Fewer ions (charges) = less conductivity

Basic solutions have similar properties

Bitter taste

Slippery

Bases have a pH Above 7

Some bases produce Hydroxide ions (OH-)

Bases cause red Litmus paper to turn Blue

Can be very dangerous if not diluted with water

Like acids, bases can conduct electricity

Strong Bases will conduct electricity better than weak bases.

Example:

◦Potassium hydroxide (KOH) is a base found in some drain cleaners.

◦KOH is a strong base & solutions will conduct electricity well (more charges/ions)

◦KOH K+ + OH-

pH values correspond to the concentration of hydronium ions & hydroxide ions.

A reaction between hydronium ions & hydroxide ions to form water molecules

The resulting solution is more neutral than either of the reactants.

Strong Acids & Bases react to form water & salt

Some acid-base reactions do not result in neutral solutions

The pH of the solution depends on the amounts of acid & base that are combined

CHAPTER 6 SECTION 4: ACIDS & BASES IN THE HOME

Bases in the home…

Soaps (emulsifier) Cleaning Products Detergents Ammonia SolutionsDisinfectants (Bleach)

OTHER ACIDS & BASES AT HOME…

Antacids are weak bases that neutralize excess stomach acid.

Shampoos are made of detergents that are able to remove dirt & oil without leaving

Know VocabularySolution

Solute

Solvent

Acid

Bases

Concentration

Molarity

Solubility

Suspension

Colloid

Know key facts about acids & bases:

Which creates H+ ions?

Which creates OH- ions?

Which can conduct electricity & why?

Which have a pH below 7?

Which have a pH above 7?

Know key facts about the types of mixtures:What are the 2 main types?

What category do suspensions & colloids fall into?

How are they similar and different?

What are immiscible liquids? Example:

What can be used to mix immiscible liquids?

Emulsifier

Example:

A mixture of a strong acid and a strong base will create…Salt & Water

Or a neutralized reactionCloser to what pH? _7_

Compare & Contrast…

Concentrated & Diluted

Saturated & Unsaturated

Polar & Nonpolar

Solubility

Know …

Its definition

How it can change based on temperature

How to read a solubility curve

This is an example of what type of reaction?

2Al + 3CuCl2 2AlCl3 +3Cu

a. Decomposition c. Double Displacement

b. Synthesis d. Single Displacement

What is the substance that gets dissolved by a solvent in a solution?

A solution is considered acidic if it contains…More hydrogen ions than hydroxide ionsMore hydroxide ions than hydronium ionsEqual amounts of hydroxide ions and

hydrogen ionsLess hydrogen ions than hydroxide ions  

A solution that has a greater amount of solvent than solute would be

Which of the following is an example of a situation in which exothermic chemical reactions occur?a. Ice cubes melt into water.b.Boiling pots of water turn to steam.c .Fireworks explode during a holiday.d. Pieces of KCl dissolve in water.

Which of the following would have an effect on the solubility of a solution?a. The surface area of the solute b. The temperature of the solventc. Stirring the solutiond. All of the above

A substance with a pH of 2 hasa. The same number of H3O+ ions as it

does OH- ionsb. More H3O+ ions than OH- ions

c. no H3O+ ions or OH- ions

d. More OH- ions than H3O+ ions

An equation that uses chemical symbols & formulas to summarize a reaction

A protein catalyst that speeds up a specific reaction

A reaction of at least 2 substances that forms a new complex compound; combines

A reaction in which a one element takes the place of another single element in a compound

. The specific substance affected by an enzyme