Chapter 2.2 By the end of this lesson you will be able to describe the properties of water and determine the differences between acids and bases using the pH scale.

Water Molecule Polarity water is polar because of the uneven distribution of electrons between the oxygen and hydrogen atoms -hydrogen is (+) -oxygen is slightly (-)

Properties of Water: polarity causes water molecules to attract other water molecules Results in: -Cohesion -Adhesion

Cohesion: attraction of a molecule that is of the same substance

Adhesion: attraction of molecules that are of different substances

Mixture -2 or more elements or compounds that are physically mixed together but not chemically combined 2 types: solutions and suspensions

Suspensions mixtures of water and undissolved material

Solution- all components are evenly distributed solute-- what is dissolved ex: salt solvent-- substance that solute is dissolved in ex: water

Is Blood a solution or suspension? Is a solution (it had dissolved components) and it is a suspension (it contains cells that don't dissolve)

pH scale -used to determine concentrations of H+ ions ranges from 0-14 Acid: (0-7)  more H+ ions Base: (7-14)  less H+ ions

Buffers weak acids or bases that counter stronger acids/bases to prevent sharp changes in pH