pH Ionization and Hydrogen Bonding

pHpH is the concentration of hydrogen ions in

a solution

Strong Acid and BaseHCl – hydrochloric acid

Strong acidH+ loses electron to Cl-Solution would have a HIGH concentration of

H+ ions

NaOH – sodium hydroxideStrong baseNa+ loses electron to OH-Solution would have a HIGH concentration of

OH- ions

BuffersWeak acids/bases that react with strong

acids or bases to have a gradual shift in the pH scale

Ex: Milk calming stomach acid

Why is water neutral?The molecule of H2O separates into

H+ loses electron to OH-Equal parts of each ion H2O has a neutral pH of 7

pH scale

DemonstrationAre the pieces of paper without water more

attracted to each other?Why are the pieces of paper with water

easier to stick together?What is holding the papers together?

Water is a polar moleculePartial negative pole and partial positive side

Hydrogen bondingDue to partial positive and partial negative

poles on the water molecule, other water molecules are attracted to each causing a hydrogen bond

Not as strong as covalent or ionic bonding

Hydrogen Bondhttp://programs.northlandcollege.edu/biolo

gy/Biology1111/animations/hydrogenbonds.html

What are the other unique properties of water?

Cohesion

Cohesion – Surface Tension

Adhesion

Adhesion - Capillary ActionHow water moves up plantsPlant tubes (xylem) are made of cellulose

which is polarWater molecules are attracted to the sides

of thin tubes of xylemWhat do you think will happen to the daisies?

Capillary ActionHow water moves

up plantsWater molecules

are attracted to the sides of thin tubes plant walls

This is also why water moves up a straw without you doing anything!

Activity!Drops of water on a pennyWhat properties of water are shown in this

experiment?