Describe water without using the word wet.

Brain Pop-http://www.brainpop.com/science/earthsystem/water/

Bell Ringer

Water is made up of atoms

Atoms attach together, or bond to form molecules.

2 Hydrogen atoms bond to 1 Oxygen atom form a water molecule ( H20)

Structure of Water

Each end of a molecule has a slight electric charge

Oxygen = slight negative charge

Hydrogen =slight positive charge

Molecule that has electrically charged areas is a polar molecule

Structure of Water

Structure of Water The positive Hydrogen ends of the water

molecule attract the negative Oxygen ends of nearby water molecules.

The end result, the water molecules tend to stick together because of the electric force; similar to an magnetic force

Capillary Action Surface Tension Universal Solvent Specific Heat

4 Key Properties of Water

Combined force of attraction among water molecules and the molecules of surrounding materials

Example: drinking from a straw {pg 48} (you will see the liquid rise higher in the straw than on the outside of the straw) OR paper towel soaking up water

Water molecules are attracted to the straw, they pull other water molecules up with them

Capillary Action

the action or property of like molecules sticking together, having an attractive force

Water molecules are attracted to other water molecules

Cohesion

the tendency of water to stick to other substances

Water can also be attracted to other materials.

Adhesion

The tightness across the surface of water that is caused by the polar molecules pulling on one another.

The tightness of the water keeps the bug from sinking

The pulling forces the surface of the water into a curved shape

Surface Tension Surface tension

causes raindrops to form round beads when they hit a car windshield

Solution is a mixture that forms when one substance dissolves another

Solvent – the substance that does the dissolving.

Many substances dissolve in water because water is polar. (like the powdered Kool-Aid)

Water is a universal solvent because it dissolves almost everything

Universal Solvent

Is the amount of heat needed to increase the temperature of a certain mass of substance by 1 degree C.

Water requires a lot of heat to increase its temperature

Water’s high specific heat is due to the strong attraction among water molecules

Specific Heat

Water is the only substance on Earth that commonly exists in all 3 states of matter◦ Solid- ice cube◦ Liquid- water in a lake◦ Gas- water vapor (humidity)

Changing State

the process by which molecules at the surface

of a liquid absorb enough energy to change into a gaseous state

Water boils at 100o C and a change of state occurs

Molecules get enough energy to escape the liquid and become invisible water vapor (gas)

Changing State- Evaporation

As water cools down, it releases some of its energy to the surroundings

Molecules slow down and temperature decreases

Condensation- process in which a gas changes to a liquid

The sweat you see on the outside of a glass

Changing State-Condensation

Liquid water freezes at 0o C

Molecules lose

energy and move more slowly

An icicle forming from water dripping off a roof

Changing State- Freezing

As the temperature reaches above 0o C the solid ice melts and becomes a liquid.

Changing State-Melting

At the end of your notes write an eight sentence summary paragraph about your notes and turn into basket

Summary