CHAPTER 2.2

SOLUTION & SUSPENSIONS

Solutions & Solutions & SuspensionsSuspensions• Water is usually part of a Water is usually part of a

mixturemixture..• There are two types of There are two types of

mixtures:mixtures:

1._______________1._______________

2. ______________2. ______________

SolutionSolutionss

SuspensionSuspensionss

SolutionsSolutions

• A _________ is a mixture in which 2 or more substances are uniformly distributed in another substance

SOLUTION

SolutionsSolutions• _____________ is the

substance dissolved in the solution– Particles may be ions,

atoms, or molecules

• _______________ is the substance in which the solute is dissolved

SOLUTE

SOLVENT

SolutionSolution

• Solutions can be composed of varying proportions of a given solute in a given solvent --- vary in concentration (measurement of the amount of solute)

• A __________________is one in which no more solute can be dissolved

SATURATED SOLUTION

WATER IS POLAR

• _______________(water solutions) are universally important to living things

• Water is the __________________

AQUEOUS SOLUTIONS

UNIVERSAL SOLVENT

WATER IS THE UNIVERSAL SOLVENT

• http://www.chem.iastate.edu/group/Greenbowe/sections/projectfolder/flashfiles/thermochem/solutionSalt.html

____________________

means “water loving”

_________ molecules try to _________ and touch water or ______________ molecules

HYDROPHILIC

“Like dissolves like”

Water makes a great solvent inliving things because so many molecules found in living things are polar or have a charge.

BE NEAR

OTHER POLAR

POLAR

NONPOLAR MOLECULES

• Nonpolar molecules do not ________ well in water.

• When they are placed in water the _____________are more attracted to ___________than to the nonpolar molecules

OIL AND WATER DO NOT MIX

DISSOLVE

WATER MOLECULES

EACH OTHER

_________________ means “water fearing”

___________ molecules try to _________ other __________ molecules and __________ ________ molecules

HYDROPHOBIC“Like dissolves like”

POLAR

Oil based paints dissolve in solvents such as turpentine . . . not water.

BE NEAR NON-POLAR

NON-POLAR

AWAY FROM

http://egullet.com/imgs/egci/nonstocksauce/nons1.JPG

The same molecule can have bothPOLAR and NON-POLARparts

EX: PHOSPHOLIPIDS

Polar head

NON-polartails

• This is very important to organisms.• The shape and function of the cell

membranes depend on the interaction of ________ water with _______________membrane molecules

POLAR NON-POLAR

CELL MEMBRANEWater crosses the cell membrane all the time.

Since it is composed of ______________molecules it will attract water but not be dissolved by water.

THIS IS A VERY GOOD THING!

POLAR AND NON-POLAR

“Like dissolves

like”

______ works because it has a _____________ that dissolves _______ and a __________ that dissolves in _____ to wash away oily dirt.

SOAP NON-polar endPOLAR ENDGREASE

WATER

SuspensionsSuspensions• Substances that Substances that

don’t dissolve don’t dissolve but separate but separate into tiny pieces.into tiny pieces.

• Water keeps Water keeps the pieces the pieces suspended so suspended so they don’t they don’t settle out.settle out.

YOUR MOST IMPORTANT SOLUTION AND SUSPENSION

Your blood is BOTH a solution and a suspension.

It has dissolved compounds in it.

Your blood cells are not dissolved in the solution. The plasma in the blood helps to hold up or suspend the blood cells.

When your heart stops pumping then the cells will fall out of suspension.

DISSOCIATION OF WATERDISSOCIATION OF WATER

• Breaking apart of the water molecule into two ions of opposite charge (due to strong attraction of oxygen atom of one molecule for H atom of another water molecule)

• H2O H+ (hydrogen ion) + OH- (hydroxide ion)

DISSOCIATION OF WATERDISSOCIATION OF WATER• A water molecule can react to form A water molecule can react to form

____________

H2O H+ + OH-

IONS

Hydrogen IonHydrogen Ion Hydroxide Hydroxide IonIon

Atoms/ions important for living things

Carbon - C 1.____________2.____________3.____________4.____________5.____________6.____________

Used to make bigger molecules

Ions = electrically charged atoms

1.____________2.____________3.____________4.____________5.____________

Oxygen - O

Hydrogen - HNitrogen - NSulfur - S

Sodium – Na+

Chloride – Cl-

Potassium – K+

Calcium – Ca++

Phosphorus - P Hydrogen – H+

ACIDS AND BASESACIDS AND BASES

•One of the most important aspects of a living system is the degree of __________ or ____________

ACIDITY

ALKALINITY

Acids are sour or tart: vinegar, lemon and orange juice, wine, aspirin.

Bases are bitter: coffee, tonic water, baking soda, antacid tablets, soap.

pH Scale

• _________________for comparing the

relative concentrations of hydrogen ions and hydroxide ions in a solution

• ranges in #’s from _________ Each pH is 10X stronger than

next

LOGARITHMIC SCALE

0-14

That means that a solution that is ph 1 is 10 times stronger than a solution that is ph 2

pH

The term "pH" was invented in 1909 by the Danish chemist Søren Sørensen.

It stands for ______________

which means "potential hydrogen".

pondus hydrogenii

The pH ScaleThe pH Scale

•pH 0 – 6.99 is an _______

•pH 7.01 – 14 is a _______

•pH 7.00 – is a ___________

ACID

BASE

NEUTRAL

WHEN pH PAPER IS USED IN LAB IT WILL TURN A PARTICULAR COLOR TO INDICATE WHETHER THE SOLUTION IS ACIDIC, NEUTRAL, OR ALKALINE.

AcidsAcids

The ________ the pH #

the _________ the ACID

The ___________ the pH #

the ___________ the ACID

Number of __________________

in solutions is ____________ than the number of hydroxide ions (OH-)

hydrogen ions (H+)GREATER

(H+) (OH-)

HIGHER

WEAKER

LOWER

STRONGER

>

AcidsAcids •EXAMPLE•HCl H+ + Cl-

Bases

The ________ the pH #

the _________ the BASE

The ___________ the pH #

the ___________ the BASE

Number of __________________

in solutions is ____________ than the number of hydrogen ions (H+)

hydroxide ions(OH-)GREATER

(H+)(OH-)

HIGHER

STRONGER

LOWER

WEAKER

>

1

23 4 5 6

REVIEW: DISSOCIATION

ACID OR BASE?

ACID OR BASE

REVIEW • the _______the pH the stronger the ACID

• the _________the pH the stronger the BASE

• pH 7.0 is__________

ACID BASE

LOWER

HIGHER

NEUTRAL

PH VALUE ? PH VALUE ? PH VALUE ?

What does the arrow indicate?

What does the arrow indicate?

REVIEW

CONTROLLING pHCONTROLLING pH•Control of pH is very important

•Most _____________ function only within a very narrow pH

•HOMEOSTASIS is accomplished with ___________ made by the body

•Buffers keep a neutral pH (pH 7)

ENZYMES

BUFFERS

• Buffers _________ small amounts of either an acid or base added to a solution

pH VALUES

NEUTRALIZE

Complex buffering systems maintain the ______________of your body’s many fluids at normal and safe levels

BUFFERS

•We have “added” special buffers to medications to help with keeping the pH in the stomach neutral.

pH IN YOUR LIFE

pH AND YOU• Human blood pH should be slightly alkaline 7.35 -

7.45. • Below or above this range means symptoms and

disease. • If blood pH moves below 6.8 or above 7.8, cells

stop functioning and the body dies. • The body therefore continually strives to balance

pH. (HOMEOSTASIS)• When this balance is compromised many problems

can occur.

PROBLEMS WITH ph: ACIDOSIS

THIS IS EXTRA STUFF: DO NOT HAVE TO KNOW FOR THE TEST

THIS IS WHY PARENTS AND TEACHERS ARE ALWAYS “NAGGING” YOU TO EAT THE PROPER FOODS!

YOUR PARENTS LOVE YOU AND TEACHERS CARE ABOUT YOU---BUNCHES!

NEXT YEAR IN CHEMISTRY YOU WILL LEARN A LOT MORE ABOUT PH.