Properties of Water

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Slide 1

The Chemistry of Life

Properties of Water

Slide 2

The Water Molecule

Neutral Charge � ZERO

Have no charge

Have an Equal number of p+ and e-

Charges aren�t evenly distributed

Slide 3

The Water Molecule

Polarity

A water molecule is polar because there is an uneven distribution of electrons between the oxygen and hydrogen atoms.

(-)

(+)

Slide 4

Hydrogen Bonds

Polar water molecules act like magnets and attract each other

Hydrogen Bonds

The attraction of the Hydrogen end (+) of one molecule for the Oxygen end (-) of another water molecule.

They are strong bonds that form between molecules (CO2, H2O, �)

Slide 5

Hydrogen Bonds

Slide 6

Cohesion

The attraction between molecules of the same substance (e.g. water).

H2O attracting other H2O molecules

Allows some insects and spiders to walk on water.

Slide 7

Adhesion & Capillarity

Adhesion - Attraction between H2O molecules and different molecules

Cohesion & adhesion produce Capillarity (upward movement against gravity of water through small tubes)

Question: How do plants make use of Capillarity?

Slide 8

Solutions & Suspensions

Water is usually part of a mixture.

Because so many things dissolve in water, it is called the Universal Solvent

There are two types of mixtures:

Solutions

Suspensions

Slide 9

Properties of Solutions

Ionic compounds disperse as ions in water (+ions & -ions spread out among polar water molecules)

Solutions are Evenly distributed mixtures

SOLUTE

Substance that is being dissolved

SOLVENT

Dissolving Substance for the solute

Slide 10

Ionic Solutions

Na+ ions will be attracted to WHAT END of the water molecule?

Slide 11

Suspensions

Substances that don�t dissolve but separate into tiny pieces.

Water keeps the pieces suspended so they don�t settle out.